Unbeaten Kazakh middleweight superstar Gennady Golovkin earned his 20th straight knockout as he dispatched Willie Monroe Jr at the Forum in Inglewood, California.

Golovkin, who has the WBA crown with his win, is now 33-0 and reinforced his claim to be one of the best pound-for-pound fighters on the planet with a devastating display.

The bout lasted six rounds, though it could have been finished off sooner had Golovkin not toyed with his foe.

A superb left-hook downed Monroe as early as the second round, and as soon as he regained his feet he was knocked back again with a powerful right.

From then on there was only going to be one winner, with the end coming as a devastating series of rapid uppercuts and hooks forced Monroe against the ropes and prompted the referee to step in.

"I'm done," Monroe gasped to the referee, and the fight was brought to a close. “Willie is a real good fighter," said Golovkin after bearing the southpaw.

"I respect him because he is not scared. I wanted to show my fans how I can beat any style.” Monroe paid tribute to the winner, admitting that he had been thrown off early on.

"I got off my game-plan when I got caught with a good shot,” he said. "I was getting hit in the kidneys and the hips and I couldn’t feel my legs.”

Next up for Golovkin is likely to be Miguel Cotto or Saul 'Canelo' Alvarez, with Carl Froch an outside chance if he chooses not to retire - and Golovkin is eager to take on the biggest names at his weight sooner rather than later.

"I want Canelo or Cotto now,” said 33-year-old Golovkin. "Not in the future.”

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