The popular Mexican landed heavy shots from start to premature finish – enhancing his record to 45-1-1 – although American underdog Kirkland was on target with some blows of his own before being laid out by a thunderous right hook in the middle of round three.
“This was one of the best knockouts of my career,” said 24-year-old Alvarez said following the fight.
“He came out with a little bit of a different style than I was expecting, but I was able to adjust and get the knockout. I knew he was strong fighter but he surprised me with his aggressiveness in the first and second round. I fight for the fans, and I’ll fight anyone, anywhere, anytime.”
Kirkland, 31, said: “I didn’t know I was knocked out.
“I had him trapped and hurt in the corner in the first round but he escaped, I had him hurt in the second also. He’s a great champion, I’m proud that I was able to compete in such a terrific event, and I hope to fight him again someday. I’m a warrior, I’ll be back.”
Elsewhere on the card at the Minute Maid Arena,??7ft tall Chinese heavyweight sensation Taishan Dong moved his record to 4-0 with a majority decision over Jamal Woods after a four-round slugfest.
“I feel really thrilled to be representing the millions of people in China today especially on one of the most attended cards of the year,” Taishan said.
“I feel like my opponent had more experience than I do but that doesn’t mean he was more skillful. Today, my strength, reach and powerful jab was what got me the win.”