Manny Pacquiao solidified his status as the sport’s best fighter with his awe-inspiring second-round knockout of Ricky Hatton on Saturday in Las Vegas.

The victory earned Pacquiao (49-3-2, 37 knockouts) THE RING’s world junior welterweight championship — his sixth title (three RING belts; four of the alphabet variety) in as many weight classes — and justified his No. 1 position in THE RING’s Pound-for-Pound Top 10, where he has been rated longer than any other fighter currently on the elite list.

Pacquiao has been in THE RING’s pound-for-pound rankings for 283 consecutive weeks (almost 5¾ years), dating back to his breakthrough first victory over Marco Antonio Barrera in November 2003.

No other fighter currently rated on the pound-for-pound list comes close to matching Pacquiao’s amazing longevity. In fact, only two other fighters have more than 100 consecutive weeks in the ratings, No. 3 Bernard Hopkins (152) and No. 2 Juan Manuel Marquez (112), who just happens to be Pacquiao’s chief rival.

Earlier this year there had been some debate among hardcore fans and boxing media as to whether the pound-for-pound top spot that Pacquiao has held since Floyd Mayweather Jr.’s retirement last summer should belong to Marquez.

Those backing Marquez pointed out that many observers thought the veteran technician won the split-decision loss to Pacquiao in their hotly contested 130-pound rematch last March.

The Marquez supporters were also more impressed with the Mexican master’s jump to lightweight, where he won THE RING championship by knocking out Joel Casamayor last September, than they were of Pacquiao’s brief foray into the 135-pound division, where he picked up an alphabet belt by battering David Diaz.

They respected Marquez’s thrilling come-from-behind KO of Juan Diaz in February more than Pacquiao’s one-sided thrashing of Oscar De La Hoya last December.

Casamayor is a far superior fighter than the tough-but-limited David Diaz, and the crafty Cuban vet (who suffered his first KO defeat against Marquez) made for a more dangerous first fight at lightweight, they said.

Juan Diaz didn’t have De La Hoya’s name or fame but the young, hungry lightweight contender was a tougher challenge and made for a much better fight than the faded superstar provided Pacquiao, the Marquez supporters added.

They made valid points.

However, the painfully one-sided beating Pacquiao administered to Hatton, who was on the pound-for-pound list and is still in his prime, and the chilling finality of his one-punch KO put an end to the debate for now.

While Pacquiao’s opposition might not quite equal that of Marquez’s recent foes, the former flyweight titleholder’s ability to jump back and forth between weight classes and the dominating fashion in which he’s won his recent fights personifies the term “pound for pound”.

Beginning with the Marquez rematch, Pacquiao has competed in four different weight classes in his last four fights — junior lightweight, lightweight, welterweight and junior welterweight — and his performances against solid-to-excellent opposition earned him Top-5 RING ratings in each division.

Pacquiao’s the man for now. There’s no debating that.

At least until Marquez takes on the comebacking Mayweather Jr. on July 18.

POUND-FOR-POUND SHAKEUP

Hatton, who was ranked No. 8 last week, was jettisoned from the pound-for-pound rankings, which, along with the departure of THE RING’s 108-pound champ Ivan Calderon, made room for two new additions to the Top 10.

Two-time welterweight titleholder Miguel Cotto (33-1, 27 KOs) returned at No. 7, and flyweight titleholder Nonito Donaire (20-1, 13 KOs) entered at No. 8.

There was also some reshuffling in the Top 10 as Israel Vazquez (No. 4 last week) switched places with Shane Mosley (No. 5 last week), unified titleholder Vic Darchinyan moved from No. 10 to No. 9, and Celestino Caballero slipped from No. 9 to No. 10.

“Ricky Hatton’s knockout loss to Manny Pacquiao knocked him out of the pound-for-pound ratings and presented an opportunity to overhaul THE RING’s Pound-for-Pound Top 10,” said THE RING editor Nigel Collins. “We dropped Ivan Calderon (No. 7 last week), who fights infrequently and is scheduled to face Rodel Mayor, a weak challenger who has lost three of his last six fights. Calderon is a brilliant defensive boxer and a legitimate world champion, but is simply not doing enough to maintain his position among the best of the best.

“Israel Vazquez, THE RING junior featherweight champion, has not fought since his amazing rubber-match victory over Rafael Marquez in March 2008. As Vazquez had a legitimate eye injury, which required multiple surgeries, he retains his status as world champion. Nonetheless, he has been demoted from No. 4 to No. 5 due to his lengthy inactivity.

“Nonito Donaire makes his pound for pound debut at No. 8. Inactivity had hampered THE RING’s No. 1 flyweight’s entry, but his recent KO of previously undefeated Raul Martinez confirmed that his 2007 knockout over Vic Darchinyan was no fluke.

“Miguel Cotto, who was dropped following his TKO loss to Antonio Margarito, returns at No. 7 due to the cloud of suspicion hanging over all of Margarito’s victories since he was caught trying to load up his hands prior to his KO defeat by Shane Mosley, who has advanced from No. 5 to No. 4.”

DIVISIONAL UPDATES

WELTERWEIGHT:

Pacquiao (No. 5 last week) moved to junior welterweight, which boosted all fighters rated No. 6 and below last week up one rung each and made room for undefeated Vyacheslav Senchenko (29-0, 20 KOs) of Ukraine to debut at No. 10.

JUNIOR WELTERWEIGHT:

Pacquiao is the new RING magazine 140-pound world champion thanks to his spectacular second-round knockout of Hatton, who drops to No. 2. The title change and Hatton’s demotion pushes down all fighters rated No. 2 or below last week one spot each and forced out Nate Campbell (No. 10 last week).

Doug Fischer can be reached at [email protected]