Manny Pacquiao's performances have steadily declined in his last four bouts. He failed to stop an over-the-hill Shane Mosley in May 2011, was arguably out-slugged by Juan Manuel Marquez in November 2011 and outpointed by Timothy Bradley in June.
When Marquez viciously knocked him out in the sixth round of their fourth fight, it appeared to be rock bottom for Pacquiao.
If Pacquiao continues to fight top competition, he will find that there are still lower depths he can descend to. Considering all he's accomplished, his age and his various personal and professional obligations, Pacquiao isn't in position to improve.
His head movement and boxing ability looked sharp through the first two rounds of his latest bout with Marquez. Ultimately, Pacquiao reverted to the slugging style that has made him so exciting throughout his career.
That was his downfall.
He can't help it. This is always the fight he'll wind up fighting. This is the reason Marquez was able to score the only clear victory in the two fighter's four-part series.
Though he is obviously quicker than Marquez, Pacquiao's desire to exchange plays into his rivals' hands. He can't resist this tendency, and Marquez knows it. He said as much in what proved to be a prophetic interview on ESPN's First Take.
He has Pacquiao's number now, and a fifth fight would likely render the same type of result.
We also have to consider what suffering such a brutal KO loss does to a fighter's psyche. That right hand from Marquez was a life-changer. Fighters of Pacquiao's caliber rarely fall victim in that way.
Ricky Hatton's career and life was changed when Pacquiao brutally stopped him in their 2009 bout. Jermain Taylor was never the same after Kelly Pavlik crushed him in the seventh round of their 2007 bout.
Although there were other factors, Mike Tyson was never the same after being upset by Buster Douglas in 1990.
Facing this type of defeat can bring an unhealthy amount of fear into the ring for a fighter. Even someone as seemingly fearless as Pacquiao can fall victim to this.
These are not machines that dust themselves off and return as good as new, no matter the damage taken in the previous bout. There are huge psychological factors involved, and none of them favor Pacquiao.
Amid requests from his family to quit, per USA Today, spiritual conflicts, per Yahoo! Sports, age and the natural fall-off involved in a long career, things aren't looking up for the future Hall of Famer.
Pacquiao would be wise to hang up the gloves now, or to take one or two easier fights so he can retire on a winning note.
The era of the great Pac-Man is done. It's time for him to make the transition to being Manny Pacquiao.
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