LAS VEGAS — Tim Bradley's trainer, Joel Diaz didn't mince words when asked if Saturday night's rematch at the MGM Grand Garden Arena could spell retirement for Manny Pacquiao, whom Bradley dethroned as WBO welterweight beltholder by split decision in June 2012.

After falling to Bradley, Pacquiao was knocked out in the sixth round by Juan Manuel Marquez in December 2012, then rebounded with November's unanimous decision over Brandon Rios.

Bradley, meanwhile, defeated Pacquiao, rose from a 12th-round knockdown to unanimously decision Ruslan Provodnikov last March, and won by split decision over Marquez, against whom Pacquiao is 2-1-1.

"That is what we're here for. I think it's Manny Pacquiao's last fight," said Diaz, to a group of reporters on Wednesday. "Like everything in life, everything has a beginning and there's an end. I think this is Manny Pacquiao's end."

NSAC TO NAME KEITH KIZER'S REPLACEMENT ON SATURDAY

On Saturday, the Nevada State Athletic Commision could name its replacement out of five candidates for Keith Kizer, who resigned in January after nearly eight years as Executive Director, NSAC chairman Francisco Aguilar confirmed to RingTV.com on Wednesday.

Kizer vacated his post to return to the Nevada Attorney General’s office, which he said he originally left to begin serving as the replacement for long time NSAC head Marc Ratner on June 1, 2006. The executive director oversees combat sports, including mix martial arts.

Five finalists have been identified from a list of nine candidates (and approximately 350 applications) and will be interviewed by the NSAC on Saturday, according to Aguilar.

"The commission's doing interviews on Saturday and we have five candidates," of a position whose annual salary pays $94,000, according to the Las Vegas Review Journal.

The finalists are Bob Bennett of Las Vegas, Andrew Foster of Sacramento, Calif., Michael Martino of Reno, Jeffrey Mullen of Germantown, Tenn., and Mark Smith of Las Vegas.

WILFREDO VAZQUEZ JR.-MARVIN SANSONA II ON SERGIO MARTINEZ-MIGUEL COTTO CARD

LAS VEGAS — Featherweights Wilfredo Vazquez Jr. and Marvin Sonsona will fight a rematch of Vazquez's fourth-round stoppage victory from February 2010 on the undercard of Sergio Martinez's defense of his RING and WBC middleweight championships against Miguel Cotto on June 7 at New York's Madison Square Garden on HBO Pay Per View, promoter Sampson Lewkowicz informed RingTV.com on Wednesday.

A southpaw from General Santos City, Philippines, Sonsona (18-1-1, 15 knockouts) has won four straight fights, including three of them by knockout, since falling to Vazquez (23-3-1, 19 KOs), who has gone 5-3 with four stoppage wins since their last meeting.

Lewkowicz, an advisor to Martinez, is in town for Saturday night's Bradley-Pacquiao II fight.

"I believe that Marvelous Marvin Sonsona can follow in the footsteps of Manny Pacquiao," said Lewkowicz, "and that he will avenge the only loss that he has."

WBO GIVES UPDATE ON GARY RUSSELL JR.-VASYL LOMACHENKO

WBO President Francisco "Paco" Valcarcel provided an update on the negotiations between Golden Boy Promotions and Top Rank Promotions, whom he granted 30 days on March 20 to make a featherweight bout featuring Gary Russell Jr. and Vasyl Lomachenko for the organization's vacant title.

With Russell being represented by Golden Boy and Lomachenko by promotional rival Top Rank, Valcarcel acknowledged that negotiations were likely to go to purse bid.

On Wednesday, while in attendance at the final press conference for Bradley-Pacquiao II, Valcarcel provided an update to RingTV.com.

"They're still negotiating. I know that [Top Rank Vice President] Carl Moretti has called [Golden Boy Vice President and matchmaker] Eric Gomez and that they're talking about the fight but they need an answer. Probably on Monday, we'll send a letter to both camps because we want to know how the negotiations are now," said Valcarcel.

"We need to know the status of the negotiations. If nothing happens, then we're going to have a purse bid after Monday. That means that after 10 days from April 14, we're going to have a purse bid if they do not have an agreement. Monday, I'll contact both parties and we want to know the status of the negotiations. I talked to Eric and I've talked to Moretti officially."

A 2008 U.S. Olympian [Russell qualified for the team but never competed due to missing the weigh-in] who is coming off a knockout of Miguel Tamayo in January, Russell (24-0, 14 KOs) was declared by Valcarcel in October to be the WBO’s mandatory challenger to face then-beltholder Orlando Salido.

The ruling did not preclude Salido from making a voluntary defense against Lomachenko, which he did on March 1. Lomachenko fell by split decision to Salido, who lost his WBO belt at the scales after failing to make the 126-pound weight limit.

As a result of Salido's failure, the title became vacant though Lomachenko was eligible to win it had he been victorious.

Lomachenko had said he wanted to make history by becoming a titleholder what was billed as his second professional fight. According to Fight Fax Inc., Lomachenko is actually 7-1 because he was paid to take part in six "World Series of Boxing" contests.

LEMIEUX-GUERRERO, LACY-BETERBIEV ON ADONIS STEVENSON-ANDRZEJ FONFARA UNDERCARD

Canadian middleweight David Lemieux (31-2, 29 KOs) will face Fernando Guerrero (26-2, 19 KOs); light heavyweight Artur Beterbiev (4-0, 4 KOs) will be in against former super middleweight titleholder Jeff Lacy (26-4, 18 KOs) and 175-pounders Eleider Alvarez (14-0, 8 KOs) and Radivoje “Hot Rod” Kalajdzic (15-0, 10 KOs) will meet on the undercard of the May 24 Adonis Stevenson-Andrzej Fonfara main event in Montreal, Quebec, Canada on Showtime, promoter Yvon Michel announced on Wednesday.

EDWIN RODRIGUEZ RETURNS ON MAY 24 AGAINST MARCUS JOHNSON ON HBO

Super middleweight Edwin Rodriguez (24-1, 16 KOs) will face Marcus Johnson (26-2, 16 KOs) on May 24 on HBO, according to ESPN.com. Rodriguez was last in the ring for a unanimous decision loss to RING champion Andre Ward in November and Johnson is 2-2 in his past four bouts, coming off last month's fourth-round technical knockout of Terrance Smith.

IBF, JOHNRIEL CASIMERO AIDE TYPHOON RELIEF

The IBF/USBA will run a fund raising campaign in the name of light flyweight champion Johnriel Casimero for the victims of Typhoon "Yolanda" in Ormoc City, that the organization's 31st Annual Convention on May 21, when Casimero will be recognized for his three successful title defenses, the organization announced on Wednesday.

The "Casimero Aid to Ormoc City" is in place to generate funds for the Philippines-based International Pharmaceuticals Incorporated Foundation (IPI), a charitable faction selected by Casimero.

The goal is to raise $4,500 (US) for the "Sustainable Container Gardening Program" in order to equip 100 households of Yolanda survivors with the ability to grow fresh, sustainable vegetables in their backyards.

Casimero is "an excellent boxer, a remarkable sportsman and we are proud that he is one of our champions," said IBF President Daryl Peoples. "It is an honor to do this in his name."

Casimero has a May 3 defense of his belt against Mauricio Fuentes.