Photo by Alex Goodlett/Getty Images

BROOKLYN — Hugo Centeno looked like he was on his way to a boring 10-round decision against James De La Rosa but the unbeaten junior middleweight prospect abruptly ended the HBO-televised bout with an overhand left that stopped the Texas native at the end of Round 5 on Saturday at Barclays Center.

Centeno (22-0, 12 knockouts), a 6-foot-1 switch-hitter from Oxnard, California, scored a first-round knockdown (from a jab) and appeared to be in command of the fight by keeping De La Rosa (23-3, 13 KOs) on the outside with his long jab and by tying up the more experienced fighter on the inside.

It was not an eventful fight and the crowd at Barclays let that be known. However, their boos quickly turned to “oohs and aahs” when Centeno switched from orthodox to southpaw and landed a left that dropped De La Rosa face first to the canvas. Referee Pete Santiago waved the fight off immediately at 2:20.

“My timing was perfect,” Centeno, 23, said. “I’ve been practicing switching to southpaw and my left hand and it landed beautifully. I felt it.”

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