Marquez's ultimate goal is a showdown with Pacquiao, who lost via split decision to Tim Bradley in June 2012. Pacquiao, against whom Marquez is 1-2-1, regained the belt with last month's unanimous decision over Bradley. A win over Pacquiao would make Marquez the first Mexican fighter to earn a fifth belt in as many weight divisions.

Marquez was last in the ring for a split decision loss to Bradley last October, which followed his sixth-round stoppage of Pacquiao in December 2012.

A 33-year-old from Denver, Alvarado (34-2, 23 KOs) is 1-2 over the course of his past three fights, all of which happened as a junior welterweight.

Alvarado was stopped in the seventh round by Brandon Rios in October 2012, won their rematch for the WBO's vacant 140-pound belt by unanimous decision last March, and then lost the title by tenth-round knockout to Ruslan Provodnikov last October.

Marquez (55-7-1, 40 knockouts) went 12-0 with nine knockouts at the Great Western Forum — now simply The Forum, having been renovated to the tune of $40 million under the new ownership of Madison Square Garden. The run started with a first-round stoppage of Martin Ochoa in January 1995 that made Marquez 9-1 with seven knockouts following his American debut.

Though losing his professional debut by disqualification, Marquez was 29-1 with 22 knockouts after his final bout at the Great Western Forum — a second-round knockout of Wilfredo Vargas.

Marquez lost his 31st fight by unanimous decision to Freddy Norwood at the Mandalay Bay Resort and Casino in Las Vegas, representing a failed bid to win the WBA 126-pound belt in September 1999.

RingTV.com sought the opinions of 27 boxing insiders as to what will transpire in Marquez-Alvarado.

Mike Coppinger, RingTV.com/USA Today

Juan Manuel Marquez TKO Mike Alvarado: Mike Alvarado will be game and should test Juan Manuel Marquez at times but we're talking about two different classes of fighters here. Even at 40, JMM is a master counter-puncher and a bigger puncher than ever.

Marquez should be able to deal with Alvarado's crude style while firing back with even bigger shots. I expect a mismatch in which Marquez doles out a beating and positions himself for yet another bout with Manny Pacquiao.

Record: 2-0 [Last pick: Pacquiao SD 12 Bradley]

Jake Donovan, BoxingScene.com

Juan Manuel Marquez late TKO Mike Alvarado: I expect this to be a close fight regardless of the outcome but can see Juan Manuel Marquez surging ahead in the second half, slowly picking apart Mike Alvarado and eventually stopping him on cuts.

Record: 7-4 [Last pick: Arreola mid-round KO Stiverne]

Coyote Duran, copy/content editor of RingTV.com/Maxboxing.com

Mike Alvarado TKO 9/10 Juan Manuel Marquez: For those fans who tire at the thought of Juan Manuel Marquez facing Manny Pacquiao a fifth time, Mike Alvarado might just be your brand of energy drink.

Though he's not the caliber of boxer Marquez is, he is younger, stronger and has much to lose in this affair. Marquez has never truly settled in as a junior welterweight.

But as far as weight classes are concerned, with a catchweight of 144 pounds locked in, not only will "Mile High" Mike still have power, he'll likely be more comfortable at the weigh-in.

Look for Alvarado to pack on another 10 pounds come fight night and render Marquez's counter-punching lucky at best. Alvarado, an underrated distance guy, pulls off a TKO win in nine or 10.

Record: 3-0 [Last pick: Bernard Hopkins UD 12 Beibut Shumenov]

Norm Frauenheim, THE RING magazine, www.15rounds.com

Mike Alvarado TKO 10 Juan Manuel Marquez: Juan Manuel Marquez is unbeaten at The Forum, going 12-0 between 1994 and 1999. But it was a different place then and Marquez is a different fighter now. Aging arenas can be rebuilt. But it’s not that simple with an old fighter.

Marquez is 40. Over the last few years, he is known for one thing: The right that knocked out Manny Pacquiao. But that's it. His counter seemed to have lost some of its timing in a loss to Tim Bradley. Even before stopping Pacquiao, he was on the perilous edge of getting stopped himself.

At 33, Alvarado has mileage on him. But Marquez won’t rough him up the way Ruslan Provodnikov did. Alvarado is younger. More important, he’s bigger. Look for him to be patient early and aggressive late in Marquez’s last fight before his Hall of Fame induction.

Record: 10-4 [Last pick: Stiverne UD 12 Arreola]

Jeffrey Freeman, www.KODigest.TV

Juan Manuel Marquez UD 12 Mike Alvarado: When I first heard this fight announced, I worried for the health of Mike Alvarado after engaging in five consecutive ring wars without adequate respite. The beating he endured last October at the hands of Ruslan Provodnikov was alarming.

Alvarado could very well be a "shot" fighter until he proves otherwise. And this match-up might very well be a mismatch until proven otherwise. Anyone ever heard of a tune-up?

Juan Manuel Marquez is nothing if not remarkably resilient. The Mexican icon has never lost back-to-back fights or been stopped and I don't expect him to start now. This is not Manny Pacquiao or Tim Bradley he's facing.

In this uneven feeling encounter, I am expecting the superior resiliency and professionalism of Marquez to be deciding factors. Team Marquez will be ready on fight night with a solid plan to win.

Team Alvarado will be fortunate if "Mile High Mike" makes the catchweight and enters the ring in a state of physical and emotional well being. Marquez outclasses Alvarado and wins on points.

Record: 10-4 [Last pick: Stiverne W 12 Arreola]

Tom Gray, RingTV.com

Juan Manuel Marquez UD 12 Mike Alvarado: I thought Juan Manuel Marquez finally started to look his age in the bout with Tim Bradley but it was the style confrontation, more than anything else, which caused him real problems.

Bradley boxed cautiously, relied on his speed and reflexes and took away the Mexican's counter-punching opportunities. Mike Alvarado cannot beat the 40-year old Marquez at that game. Alvarado will be completely outclassed if he attempts to play high-speed chess.

That's why Alvarado will take chances and opt for a shootout when he sees no other way to win. I see Alvarado earning his money in this one but he still hears the final bell.

Record: 11-2 [Last pick: Stiverne UD 12 Arreola]

Lee Groves, RingTV.com

Juan Manuel Marquez W 12 Mike Alvarado: To me, this is truly a toss-up fight. Although Juan Manuel Marquez hasn't fought at the Forum in 15 years, he will enjoy an edge in intangibles because of the sentimental feelings he has for the site as well as boasting a big advantage in crowd support.

Mike Alvarado is younger and faster and if he applies the Timothy Bradley blueprint throughout the fight, he may well out-box Marquez, who will turn 41 in August.

But Alvarado is a warrior at heart and thus, sometime during the fight, he will try to push the action. And if he pushes the action, Marquez will assume the counter-punching role he prefers. Therefore, Marquez will do just enough to win a hard-fought decision.

Record: 4-3 [Last pick: Hopkins UD 12 Shumenov]

Andreas Hale, KnockoutNation.com

Juan Manuel Marquez UD 12 Mike Alvarado: This is the curious case of Juan Manuel Marquez acting his age versus Mike Alvarado's body betraying his mind. When he flattened Manny Pacquiao, Marquez looked as if he drank out of the Fountain of Youth and summoned the hammer of Thor. But when he faced Timothy Bradley, Marquez looked slower, older and appeared to be fighting Father Time more than he fought Bradley. So which Juan Manuel Marquez will we get against Alvarado? My guess is more of the latter than the former.

Still, this version of Marquez should be able to counter effectively against the steel-willed Alvarado. When they meet in the ring, Alvarado should feel the effects of being in two wars against Brandon Rios, a pummelling by Ruslan Provodnikov, a rock 'em/sock 'em affair with Mauricio Herrera and a remarkable come-from-behind victory against Breidis Prescott. That's 49 rounds of slugging it out. That's just way too many rounds of your brain slamming around in your skull than I'd like to see.

Marquez's impeccable timing should be the difference-maker in this fight as he'll find space to counter through the middle rounds and possibly drop Alvarado late. It will be similar to Marquez's war with 2009 showdown with Juan Diaz but Alvarado should make it to the final bell in a spirited but losing effort. 

Record: 11-2 [Last pick: Mayweather UD 12 Maidana]

Keith Idec, The Record/BoxingScene.com

Juan Manuel Marquez UD 12 Mike Alvarado: Juan Manuel Marquez is seven years older than Mike Alvarado and has fought 63 times as a pro. He still might be the fresher fighter Saturday night.

Alvarado has engaged in three straight brutal fights and lost two of those by technical knockout. He'll own a significant size advantage over Marquez, which makes him dangerous.

But Alvarado will have too much difficulty dealing with Marquez's counter-punching to out-point the Mexican legend. Alvarado will make enough of a brawl out of this 12-round fight to make it reasonably competitive, but won’t win.

Record: 10-3 [Last pick: Mayweather UD 12 Maidana]

Ryan Maquinana, CSNBAYAREA/BoxingScene.com

Juan Manuel Marquez UD 12 Mike Alvarado: It's easy to write off Mike Alvarado because of Juan Manuel Marquez's supreme boxing skills but I think the Denver native will make the Mexican star fight in spurts early on.

I just feel that Marquez will grow increasingly accurate as the fight goes on and befitting his age, he'll pick his spots and make it to the finish line convincingly ahead.

Record: 2-0 [Last pick: Khan UD 12 Collazo]

Rich Marotta, KFI Radio, Los Angeles

Juan Manuel Marquez UD 12 Mike Alvarado: A very legit fight with the winner definitely not assured. As in most Juan Manuel Marquez fights, it will be up to the opponent to dictate the type of fight we will see stylistically.

The best chance for "Mile-High" Mike Alvarado is if he utilizes the boxing techniques he did against Brandon Rios in their rematch. He needs to jab, move, put together combinations, pivot and and get out. 

If he decides to slug, which is more in his natural wheelhouse, then he may be playing right into Juan Manuel's hands. Marquez makes those who come to him and slug pay for it. However, throughout his career, the guys who have made it toughest on him have been boxers and movers.

I think Alvarado will fight smart for awhile but as the fight wears on, Marquez will induce him into trading at times and Juan Manuel is so damn smart and clever, he will take over. Marquez will dominate in the late rounds and win a decision.

Record: 9-5 [Last pick: Arreola W 12 Stiverne]

Diego Morilla, XN Sports

Juan Manuel Marquez TKO 10 Mike Alvarado: Juan Manuel Marquez may be way past his prime and feeling the effects of the many wars through which he has put his aging body but he still has more than enough to beat Mike Alvarado.

Alvarado is a tough-as-nails but flat-footed fighter who takes an enormous amount of punishment. It could be a decision or a cuts-induced stoppage but Marquez will certainly prevail with his aggressive style and his still-awesome ring savvy.

Record: 0-1 [Last pick: Arreola UD 12 Stiverne]

Jack Obermayer, Fight Fax Inc.

Juan Manuel Marquez W 12 Mike Alvarado: Juan Manuel Marquez still has smarts; Mike Alvarado not as much. It is brains over brawn.  Marquez by decision.

Record: 7-1 [Last pick: Mayweather UD 12 Maidana]

John J. Raspanti, Doghouseboxing.com/KO Monthly Magazine/examiner.com

Juan Manuel Marquez W 12 Mike Alvarado: This is another pick 'em fight but I'm giving the edge to Juan Manuel Marquez. Mike Alvarado was brutalized by Ruslan Provodnikov in his last bout. Marquez lost a relatively close decision to Tim Bradley.

Alvarado is the younger fighter by seven years but he might be older as far as damage goes. I see a close fight with Marquez doing a little bit more down the stretch to notch the victory.

Record: 10-4 [Last pick: Arreola SD 12 Stiverne]

Matt Richardson, BoxingScene.com

Juan Manuel Marquez KO 10 Mike Alvarado: This is going to be an excellent fight for as long as it lasts. How long it lasts, however, I believe really depends on what Mike Alvarado has left. We already know what Juan Manuel Marquez has left at this stage: it's not much but is enough to beat the sluggers and slower guys.

Just keep him away from guys who can box and move. Alvarado can box and move but not nearly as well as someone like Tim Bradley and will Alvarado be able to do so anyway?  Alvarado always seems like a guy who's unsure of the game plan from round to round. Sometimes he wants to box and sometimes he wants to slug.

That should play to the benefit of the older Marquez. Alvarado is a guy who is there to be hit and Marquez should be able to hit him enough to pull out a win. It won't be pretty but it should be exciting. Marquez in 10.

Record: 9-4 [Last pick: Stiverne W 12 Arreola]

Chris Robinson, Hustleboss.com

Juan Manuel Marquez W 12 Mike Alvarado: I think Juan Manuel Marquez will find a way to hold off a very motivated Mike Alvarado in an excellent fight. I think the match will go the distance with Juan doing just enough to win with a strong second half of the fight.

Record: 3-2 [Last pick: Khan SD 12 Collazo]

Cliff Rold, BoxingScene.com

Mike Alvarado KO Juan Manuel Marquez: There's no question who the greater fighter is. That's Juan Manuel Marquez. But in Mike Alvarado, he faces the biggest world-class opponent of his career. Size doesn't win fights but it can make a difference in a physical affair.

Marquez knows that and it's why there is a catchweight of 144 despite Alvarado technically coming up in weight to him. Alvarado at 144 will be the heaviest he's been since 2010.

Marquez has been drawn into multiple wars more frequently since moving above 126. At 40, this is one too many and Alvarado is in a more must-win position. It will probably go late but Alvarado scores the upset.

Record: 8-5 [Last pick: Mayweather UD 12 Maidana]

Michael Rosenthal, THE RING Magazine

Juan Manuel Marquez UD 12 Mike Alvarado: I think Juan Manuel Marquez will have to work hard but he's the better all-around fighter than Mike Alvarado, even at the age of 40. Marquez by close but unanimous decision.

Record: 7-3 [Last pick: Mayweather Jr. UD 12 Maidana]

Abel Sanchez, trainer of WBA 160-pound titleholder Gennady Golovkin

Juan Manuel Marquez UD 12 Mike Alvarado: I think Juan Manuel Marquez wins a tough fight. Mike Alvarado does well early buts gets beat up late. Marquez by unanimous decision, 114-113, 115-113, 116-112.

Record: 2-0 [Last pick: Hopkins W 12 Shumenov]

Joseph Santoliquito/THE RING Magazine/RingTV.com/CBS Sports

Juan Manuel Marquez W 12 Mike Alvarado: I still think Juan Manuel Marquez has something left but you have two guys going at it and this does have an underlying loser-is-done theme. Marquez has much more at stake than Mike Alvarado. Marquez wins a battle.

Record: 6-0 [Last pick: Khan KO 10 Collazo]

John Scully, trainer

Juan Manuel Marquez W 12 Mike Alvarado: I'm going with Juan Manuel Marquez in a definitely hard-fought 12-round decision over Mike Alvarado.

Record: 7-3 [Last pick: Arreola UD 12 Stiverne]

Ryan Songalia, RingTV.com

Juan Manuel Marquez W 12 Mike Alvarado: While I do think that Juan Manuel Marquez is past it and that Mike Alvarado has far too much mileage on his body both in and out of the ring, I still think this will be a good fight.

Could we see Alvarado take advantage of an aging Marquez, hammering a man who has hung on too long to the canvas? Yes, but I doubt it because of the way their styles match up.

Marquez loves a guy who jumps in on him and tries to destroy him and Alvarado's style plays right into his hands. Put me down for a Marquez decision win with both guys surviving trying times along the way.

Record: 1-0 [Last pick: Mayweather UD 12 Maidana]

Rob Soucy, BoxingTalk.com

Juan Manuel Marquez TKO 11 Mike Alvarado: I could see this fight playing out in a few different ways but I'll go with the future Hall-of-Famer to win an exciting fight in which he has to come off of the canvas to do so.

With a fifth fight against Manny Pacquiao hanging in the balance, I think Juan Manuel Marquez will find a way to win in order to secure one last huge payday.

If Mike Alvarado is able to take Marquez's power, I believe he can win a boxing match. But sometimes, his heart is too big for his own good. I believe we will see a great fight with the legend from Mexico down on the scorecards before stopping Alvarado.

Record: 8-1 [Last pick: Stiverne UD 12 Arreola]

Bob Velin, USA Today

Juan Manuel Marquez UD 12 Mike Alvarado: Even though Juan Manuel Marquez is now 40 and has lost two of his last four fights, he is still one of the craftiest and most intelligent boxers and precision counterpunchers in the sport.

Just ask Manny Pacquiao. Mike Alvarado is bigger than JMM and hungrier, which might be true. But unless Alvarado can knock JMM out, he will not outbox him. Thus I see it going the distance and Marquez prevailing.

Record: 7-1 [Last pick: Arreola KO 9 Stiverne]

Dominic Verdin, RingTV.com

Juan Manuel Marquez TKO 11 Mike Alvarado: Mike Alvarado is coming off an emotional and disturbing beat-down from the heavy hands of Ruslan Provodnikov. Juan Manuel Marquez is also attempting to recover from a loss to Timothy Bradley. That's where it all ends.

Marquez's loss was a debatable split decision and not a drubbing, as was the case with Alvarado. So who has the advantage? Well, it's an obvious choice to go with the fresher fighter in Marquez, who lost a well-deserved decision.

Then again, Marquez has been in some wars over a career that has spanned over 20-plus years. Alvarado could conceivably give Marquez fits with his height and next-day weight advantage.

However, at times, Alvarado tries to emulate a boxer when he's more the aggressor as in his wrestling days. He needs to stay true to his identity and not make a false appearance of being a consummate boxer, which he is not.

Marquez will stay in the pocket and trade as he does now, since the miles have tacked on over the years. That will make for an exciting war, giving the fans a tremendous prize fight.

Alvarado will dig deep and appear to have the superior position in the later rounds. Marquez, trailing on the cards, will rock Alvarado and drop him in the 11th and force the referee to halt the bout.

Record: 8-4 [Last pick: Stiverne W 12 Arreola]

Charles Villa, guest/fan, Portland, Ore.

Juan Manuel Marquez UD 12 Mike Alvarado: If these two could have somehow met in the prime of their careers, pitting the classic brawler versus a brilliant counterpuncher, this fight would have excited plenty more fans. Unfortunately, Juan Manuel "Dinamita" Marquez at age 40 is clearly at the tail end of his career while Mike "Mile High" Alvarado's place trajectory remains unsure.

The last time we saw Marquez, he had been slightly outpointed during a brilliant Timothy Bradley performance. Never one to concede defeat at the end of 12 rounds, Marquez declared after the match that a robbery had taken place. Thus, we have this fight and Marquez continuing in his quest to be the first Mexican to win titles in four titles in four different weight classes.

Alvarado doesn't seem to be chasing after history but rather the much vaunted respect most fighters seem to prize above most things. He wants to erase the image of his battered and bruised face at the end of a devastating matchup with Ruslan Provodnikov. Alvarado is never going to be mistaken as a master-class boxer but he also doesn't want the reputation of being only a face-first brawler.

Alvarado wants some recognition for the skills he does possess. But if "Mile High" wanted respect for boxing skills, he picked the wrong old man to display them against. Despite Marquez beginning to look his age against Bradley, "Dinamita" still has enough in him to counter Alvarado for days on end. Look for Marquez to put on a show for the re-opening of the Great Western Forum and earn a spirited 12-round unanimous decision.

Record: 4-4 [Last pick: Arreola UD 12 Stiverne]

Anson Wainwright, RingTV.com

Juan Manuel Marquez TKO 10 Mike Alvarado: I think Mike Alvarado will have his moments but ultimately, Juan Manuel Marquez's class tells. Marquez has the greater boxing I.Q.

I feel that will see him home in what I expect to be a fantastic fight between two warriors. Once again, Marquez will stave off Father Time to score an impressive 10th-round stoppage over the always tough Alvarado.

Record: 9-3 [Last pick: Stiverne W 12 Arreola]

By a landslide 24-to-3, the insiders favor Juan Manuel Marquez against Mike Alvarado at welterweight.

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