After more than 20 glorious years as a professional boxer, Manny Pacquiao announced Saturday, following his win over Timothy Bradley, he will retire, per Mav Gonzales of GMA News in the Philippines.

The Filipino superstar will undoubtedly go down as one of his era's best fighters. He is the only boxer to hold titles in eight different weight divisions, and in terms of pay-per-view draws, and the only man over the past two decades who can hold a candle to him is Floyd Mayweather.

It became increasingly clear over the past couple of years Pacquiao was no longer the same fighter who dominated top-flight competition in the past. He is arguably still among the best in the business, though, which is why this couldn't have been an easy decision.

With that said, Pac-Man finally accomplished what he set out to do many years ago by landing a fight with Mayweather. It was the one boxing match essentially every fan wanted to see, and Pacquiao was able to make it happen.

Prior to the contest, trainer Freddie Roach revealed retirement would be Pacquiao's best option if he managed to defeat Mayweather, according to David Mayo of MLive.com:

I would ask him to quit because there's nothing else out there. I think it would be a great way to retire and I think would be a great way to help Manny try to become president of his country, because I think he's getting close to that next year. I think he enjoys that, he likes helping people, and he wants to make his home a better place. He really does. So I kind of like that for him.

Pacquiao lost decisively to Mayweather, though, which generated even more questions regarding his future. That was compounded by the fact he suffered a torn rotator cuff that required surgery. According to ESPN.com's Dan Rafael, the procedure was expected to keep him out anywhere from nine months to a year, and Dr. Neal ElAttrache elaborated on the situation:

We have an MRI scan that confirms he has a rotator cuff tear. He has a significant tear. Once you know he has a tear that's not going to heal on its own, then the decision for an active person is you want to try to fix this before it gets bigger. If all goes as expected with the surgery and the rehab is successful, Manny could be back training in about six months.

At that point, he will be regaining strength and endurance, and competition is reasonable within nine months to a year. But this is a severe enough tear that it won't heal without being repaired.

Per BBC Sport, Pac-Man claimed the injury prevented him from performing at a peak level against Mayweather:

Deep down inside, though, Pacquiao's decision to retire suggests he knew he was no longer at the top of his game. With that said, the fact he was even able to be part of a fight against Mayweather was impressive considering what he went through in the years leading up to it.

Following consecutive losses to Bradley and Juan Manuel Marquez in 2012, many began to question if Pacquiao was reaching the end of the line. That persisted leading up to his fight against Brandon Rios in November 2013, but Pac-Man continued to shoot down any thoughts of retirement, per Sky Sports:

Pacquiao's stance conflicted with that of Roach, however. According to ESPN UK, prior to the Rios fight, Roach said retirement would be a consideration if he didn't perform well:

Despite all of the pressure on Pacquiao's shoulders entering that Rios fight, he rose to the occasion and put a stop to his two-fight losing streak. Pac-Man exerted his dominance over Rios and won in convincing fashion via unanimous decision.

That win led to another shot at Bradley with the WBO Welterweight Championship on the line. Many felt as though Pacquiao was robbed in the first Bradley fight, and he made good on that questionable loss by beating "Desert Storm" decisively in their second meeting.

Pac-Man appeared to be back on track after consecutive victories, and he entered his tilt against Chris Algieri as a heavy favorite.

Despite retirement talk almost completely evaporating following back-to-back wins, Algieri's trainer, Tim Lane, made it clear the goal was to end Pacquiao's career, per Greg Savage of Sherdog.com:

Pacquiao once again won in dominant fashion, and with three consecutive victories under his belt, it set the stage for a dream matchup with Mayweather.

Pacquiao holds victories over the likes of Erik Morales, Oscar De La Hoya, Miguel Cotto, Shane Mosley and a host of other stars. He had a few missteps along the way, but retiring now ensures his legacy is cemented.

With that said, it is still somewhat surprising to see such a huge star hang up the gloves. Boxing is undoubtedly losing one of its only remaining superstars. There are definitely some promising guys who are looking to make the leap, but Mayweather is the only fighter whose resume is as impressive as Pacquiao's.

Pacquiao, unlike most retired boxers, has plenty to occupy him outside the ring. He has a burgeoning political career in his native Philippines, as Roach mentioned, and he has even hinted toward running for president at some point.

Since there isn't much more Pacquiao can accomplish as a boxer, it's likely he'll continue to chase his political dreams. He has accomplished essentially everything possible as a boxer, and he will go down as one of the greatest pugilists in the sport's history.

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