By Keith Idec

NEW YORK – Short notice, short night.

Christopher Diaz needed less than three rounds to knock out late replacement Bryant Cruz in their scheduled 10-round super featherweight fight Saturday night in The Theater at Madison Square Garden. Puerto Rico’s Diaz dropped Cruz four times before referee Harvey Dock mercifully stopped their one-sided fight 37 seconds into the third round.

The 23-year-old Diaz (22-0, 14 KOs) also won the NABO 130-pound championship. He was supposed to face Casey Ramos (24-1, 6 KOs) on the Vasyl Lomachenko-Guillermo Rigondeaux undercard, but Ramos withdrew from the bout earlier this week for undisclosed reasons.

Cruz (18-3, 9 KOs), of Port Chester, New York, came to fight, but couldn’t deal with Diaz’s superior power.

“I felt great in my first fight at 130,” Diaz said. “This was the kind of performance I was looking for. I know that Miguel Cotto just retired, but I’m here to stay for a very long time and [I want to] become one of the best superstars from Puerto Rico. I hope I bring happiness to the people from my island after all we went through with Hurricane Maria.”

Diaz cracked Cruz with a straight right hand to the middle of his face that floored Cruz early in the first round. Cruz got up, made it to the end of the first round and tried to make the match competitive in the second round.

Diaz delivered a vicious body shot that hurt Cruz badly late in the second round. Cruz eventually went down twice more in the second, but was again able to survive serious trouble because he got up from the second knockdown of the second round with little time left in it.

Cruz came out for the third round, but didn’t last long.

Diaz buckled his knees with a left hook before flooring him for the fourth time with a left-right combination. Dock immediately waved an end to the bout, with Cruz still on his gloves and knees, trying to get up.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.