George Kambosos Jr has beaten undefeated world champion Teofimo Lopez in a major upset to claim the IBF, WBO, WBA and The Ring lightweight world champion.

Kambosos was crowned the new lightweight world champion by split decision, 115-111, 115-113, 113-114 over 24-year-old American Lopez.

In a tight tussle, 28-year-old Australian Kambosos knocked down Lopez in the first round with a overhand right-hand hit amid an energetic start, leaving the New York crowd shocked.

Kambosos defied expectations and was on top throughout the middle rounds before Lopez rallied in the ninth round with a few booming right-hand shots.

In the 10th round, Lopez dropped the Australian to the canvas with a chopping right-hand hit although Kambosos returned to his feet to fight on to victory.

"I believed in myself, I backed myself and I said it time after time," Kambosos said after the fight. “You might not believe it, but I believe in myself. Look at me now, I’ve got all of the jewels.

"Look at me now, I’ve got all the jewels. I’m not the king, I’m the emperor because I come to every other country and I take them out one by one."

Lopez disputed the result after the fight, claiming he dominated although that was met by jeers from the New York crowd.

Japanese boxer Kenichi Ogawa defeated Azinga Fuzile after dropping him three times in a dominant display to win the vacant IBF world super featherweight title in the co-main event.