Turning Stone Casino, Verona, New York - In a junior middleweight title showdown, Jaime Munguia (29-0, 25 KOs) became a new player in the weight class with a fourth round stoppage of Sadam Ali (26-2, 14 KOs) to capture the WBO junior middleweight title. Ali went down four times in the fight.

Ali was making the first defense of the title he captured last year, with an upset decision over Miguel Cotto in the Puerto Rican star's final career fight.

Munguia came in as a very late replacement for mandatory challenger Liam Smith, who withdrew with an illness. Munguia was initially targeted as an opponent for middleweight king Gennady Golovkin for May 5 - when Canelo Alvarez was suspended for a drug test violation.

Munguia came out very focused in the first round, and he went right after Ali. He scored a knockdown very quick with a combination to the head and body. Ali was caught right on the chin with a left hook. Ali got up very hurt and it didn't take long before he was dropped for a second time. Once again he made it up, and barely survived to the bell.

Ali came out a little better in the second, with Munguia going after him. The round was close until the last ten seconds - when Munguia cracked Ali with hard shots again and Ali went down for a third time as round ended. Munguia was clearly too big and too strong for Ali.

The fight was nearly stopped by officials before the start of the third.

During the third, Ali was putting his punches together well and seemed to back Munguia up. But then Ali was wobbled and seemed to go down again from a series of shots at the end of the round, but the referee ruled it as a slip.

The fight was once again nearly stopped by ringside officials before the start of the fourth.

During the fourth round, Munguia came out pressing the action, and landed another big shot that dropped Ali for a fourth time - and the fight was waved off by the referee.