By Jake Donovan

Eight-and-a-half years later, a great rivalry finally gains a definitive ending.

In a wild fight that saw both fighters hit the canvas, Juan Manuel Marquez had the final say with a vicious one-punch sixth round knockout of Manny Pacquiao in their fourth fight Saturday evening at the MGM Grand.

The one shot – a perfectly-timed counter right hand – took the fight out the judges’ hands for the first time in their tetralogy. Fans of both fighters insisted their guy to be 3-0 in the series, with each of the previous three encounters being that close and debatable.

Part four threatened to go down the same route, though less to do with outboxing each other and more to do with who can inflict the most harm.

The answer to that, surprisingly, was Marquez.

Pacquiao jumped out to an early lead, taking the opening two rounds with speed and movement. Marquez didn’t necessarily have knockout on his mind, but certainly fought with the mentality of a fighter who wasn’t going to fall prey to the judges any more in this long-running series.

A taste of that came in round three when Marquez shocked Pacquiao as well as the capacity crowd of 16,438 when a right hand dropped the Filipino for the first time in this series. Marquez had previously suffered four knockdowns – including three in their very first round together back in May ’04 – but has come across as the stronger fighter in each of the past two bouts.

Pacquiao shook off the blow but still didn’t seem all the way back. Marquez knew it was a matter of time before he would eventually close the show, but wasn’t about to rush to judgment.

“I wanted to be calm,” Marquez revealed after the fight. “After I knocked him down the first time, I had to be patient. I knew that with one punch, Manny could turn around and knock me out.”

Marquez wasn’t too far off in his logic. Pacquiao rallied back to score a knockdown of his own in a fifth round that – along with the fight and its ending – will be remembered come year-end awards time. A straight left knocked Marquez off balance, forcing the Mexican to touch his glove to the canvas. The knockdown suffered was his first in this series since being dropped in the fourth round of their March ’08 encounter.

“He caught me with a good punch,” Marquez admitted. “After that he was very quick. But I was strong and knew I had it in me to win the fight.”

The thing about Marquez’ trips to the canvas was that he always came back to outbox Pacquiao over the course of the remaining rounds in those bouts, only to come up short on the cards. The pattern didn’t at all hold up here, as he was forced to withstand another Pacquiao rally towards the end of the fifth after stunning the southpaw himself.

Stunning is one of just many ways to describe the sixth round, or at least its ending. Marquez fell back behind, as Pacquiao began to slice up his old rival. Blood was beginning to ooze as momentum appeared to swing back in the direction of the man who won more championships than any other in boxing history.

Then came the right hand heard ‘round the world.

A counter right crashed on Pacquiao’s jaw, a split second after Marquez was able to avoid the straight left ripping in his direction. Pacquiao crashed upon impact, lying face-first and motionless on the canvas as the fight was waved off.

The official time was 2:59 of round six, leaving fans and viewers in jaw-dropping disbelief. The only two who didn’t seem overwhelmingly surprised were the two fighters themselves.

“He got me with a good shot. That’s boxing. Sometimes you get hit,” Pacquiao said on TopRank.TV after suffering his second straight loss as he falls to 54-5-2 (38KO). The night marked the first time in more than a decade he suffered a stoppage, the last occurence coming in 1999, months before his 21st birthday. 

It's also his first loss against a repeat opponent, having previously gone 5-0-1 in sequels with Marquez (2-0-1), Erik Morales (2-0) and Marco Antonio Barrera (1-0).

Following the disputed points loss to Tim Bradley in June, Pacquiao was able to take comfort in the fact that so few people actually agreed with the decision. On this particular occasion, he could only rationalize on what went wrong.

“I started to get overconfident,” Pacquiao admitted. “I never expected those punches.”

Marquez did. He also expected to finally leave Las Vegas with a win against a fellow legend who has barely avoided defeat in their previous three meetings. Pacquiao was 2-0-1 in the series, even though Marquez has collectively won more overall rounds.

More than 8 ½ years after their epic first fight in this very venue, Marquez delivers a series of firsts in a four-fight set that will go down as one of the fiercest rivalries in the history of the sport.

Prior to the fight, the 39-year old Marquez, now 55-6-1 (39KO) stated that he needed a win in order to retire a happy man. When approached on the subject of what – if anything – was next, Marquez was noncommittal.

“I’m going to rest and enjoy this victory with my family. I dedicate this win to my family and to all of my fans in Mexico.”

Prior to their third fight in this same arena nearly 13 months ago, many hoped that closure would come about so that both could finally go their separate ways. Now on the heels of a definitive ending – the first of its kind in four fights – talks have already surfaced of a possible fifth fight.

There is the train of thought that the image of Pacquiao splattered on the canvas is the end of his days as a top fighter in the driver’s seat to negotiate any big fight. With that in mind, why bother sticking around when you’ve already accomplished so much, with this bout adding another $25-30 million to his bank account.

One party with a vested interest will tell you why.

“People love this action,” insists Hall-of-Fame promoter Bob Arum. “Have you seen a more exciting fight in years? This fight will go down in history as a ring classic.

“If they want to fight again, then why not?”

Because this one produced what both fighters and millions of fans have forever sought – closure.

Jake Donovan is the Managing Editor of Boxingscene.com. Follow Jake on Twitter: @JakeNDaBox