Ringside With Manny: Pacquiao wins by unanimous decision, keeps WBO welterweight belt.

AP Photo/Isaac Brekken

Manny Pacquiao dominated an overmatched Shane Mosley to retain his World Boxing Organizationwelterweight title via a lopsided unanimous decision at the MGM Grand Hotel in Las Vegas.

Pacquiao repeatedly peppered Mosley with sharp combinations, forcing the American to be on the defensive for much of the one-sided bout. The Filipino champion floored Mosley in the third round with a right straight-left hook combination from which Mosley never fully recovered. After tasting the sting of Pacquiao's punches, the former three-division champion rarely went on the offensive and spent much of the remaining rounds trying to anticipate where Pacquiao's next blows would come from.

The three judges scored it 120-107, 120-108, and 119-107.

Mosley was credited with a knockdown in the 10th round after Pacquiao fell back on his behind. Replays showed Pacquiao was pushed and it also appeared Mosley was stepping on Pacquiao's foot. But Pacquiao was so dominating that round that based on the official scorecards, none of the judges gave Mosley the standard 10-8 score.

Outside of that phantom knockdown, it was all Pacquiao. Mosley was never into the fight, unable to get any type of offense going and at times already cringing even before a Pacquiao punch landed.

Pacquiao saw his record improve to 54-3-2 while Mosley slipped to 46-7-1 with one no-contest. The fighting congressman from Sarangani is slated to face Juan Manuel Marquez on November 12, while the 39-year-old Mosley will likely retire after losing badly for the second time in his last three fights.

The undercard matches in the "Pacquiao vs Mosley Fight" have already wrapped up and here are the results, based on live streaming updates from Pay-Per-View (PPV) and before you see it on free TV:

Pier Olivier Cote (Canada) wins by 4th Round TKO vs Aris Ambriz (USA)

Mike Alvarado wins by 3rd Round TKO vs Ray Narh

Kelly Pavlik wins by major decision vs Alfonso Lopez

Jorge Arce wins by 12th Round TKO vs Wilfredo Vasquez

As for the main event of the evening, Shane Mosley off to a great start, owning the first round, but Manny Pacquiao, just like any of his fights, warms up during the first round and is now in control of the next rounds.

Round 1 for Mosley

Round 2 for Pacquiao

Round 3 for Pacquiao

Round 4 for Pacquiao

Round 5 for Pacquiao

Round 6 for Pacquiao

Round 7 for Pacquiao

Round 8 for Pacquiao

Round 9 for Pacquiao

Round 10 for Mosley (He knocked down Pacquiao on this round)

Round 11 for Pacquiao

Round 12 for Pacquiao

Manny Pacquiao wins by unanimous decision!

Highlights: Pacquiao vs. Mosley

Manny Pacquiao reacts after defeating Shane Mosley by unanimous decision during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao celebrates after defeating Shane Mosley by unanimous decision during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao reacts after defeating Shane Mosley by unanimous decision during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, left, attacks Shane Mosley against the ropes in the 11th round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas. Pacquiao won by unanimous decision.

Pacquiao of the Philippines connects on Mosley of the U.S. during their WBO welterweight title fight at the MGM Grand Garden Arena in Las Vegas

Shane Mosley is worked on by his trainers during a WBO welterweight title bout against Manny Pacquiao, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, left, throws a punch against Shane Mosley in the fourth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Shane Mosley is wiped down after losing to Manny Pacquiao after a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, right, lands a punch against Shane Mosley in the fifth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Referee Kenny Bayless, left, issues the count on Shane Mosley who was knocked down in the third round by Manny Pacquiao during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Shane Mosley, left, and Manny Pacquiao exchange punches in the second round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, right, lands a blow to the body against Shane Mosley in the eighth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, right, lands a punch against Shane Mosley in the ninth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, left, lands a punch against Shane Mosley in the seventh round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Shane Mosley lays on the mat after being knocked down by Manny Pacquiao in the third round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Shane Mosley, left, and Manny Pacquiao exchange punches in the second round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Shane Mosley, left, and Manny Pacquiao exchange punches in the sixth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, right, lands a punch against Shane Mosley in the fourth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, right, looks down at Shane Mosley who slipped during the fourth round as referee Kenny Bayless looks on during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

Manny Pacquiao, left, throws a punch against Shane Mosley in the fourth round during a WBO welterweight title bout, Saturday, May 7, 2011, in Las Vegas.

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