Crolla (30-4-3, 11 KOs) chanced upon a clear shot to the body of Perez using a massive left hook that sent the Colombian champion to the canvas. Perez tried to beat the count but failed.
“I was very confident I would get him out of there,” said Crolla. “I thought it would have been a head shot. I touched him with a right hand and sunk him with a left.
Crolla and Perez fought to a draw last July in the same venue in a clash that Crolla thought he won.
“It is an amazing feeling, it is a dream come true, now I just want many more nights like this in Manchester,” said Crolla, who was nursing a head injury early this year from burglars in his neighborhood.
“I’ve dreamed this dream since I was 10. I didn’t know it was going to be this good. It is better than I ever dreamed it would be,” he added.
Crolla, who turned pro in 2011 has been aiming for a major title fight since winning the WBO lightweight inter-continental title in 2013.
Perez (32-2-1, 20 KOs) was unbeaten when he lost to Yuriorkis Gamboa at the Bell Centre, Montreal, Quebec, losing his chance to win the WBA Interim Lightweight title which was at stake in the fight.
The 32-year-old Colombian eventually won the WBA interim title from Argenis Lopez last year via a unanimous decision. Perez defended the title three times before losing to Crolla.
Perez was on his four-fight winning streak when he fought Crolla to a draw at the Manchester Arena in Manchester, England last July.
With the win, Crolla improved his record to 30-4-3 while Perez drops to 32-2-1.
