Former world champion Paul Butler has given high praise to Naoya Inoue.

The two boxers collided on Tuesday night in Japan, with Inoue battering Butler for an eleventh round knockout to become the undisputed world champion at bantamweight - with the WBC, IBF, WBA, WBO world titles coming together.

Inoue, who is a three division world champion, improved his record to 24-0 (21 KOs).

The Japanese star is now looking to move up in weight to 122-pounds to pursue a fourth divisional title.

“You can see the punches coming but sometimes you can’t react quick enough to get out of the way, because he is that fast. That’s what really good fighters do — they have good timing, good accuracy and good speed, and sometimes you just can’t get out of the way of that," Butler stated, according to ECHO.

“He’s quite ignorant in his defense. He knows he’s got punching power and he knows he’s got a good chin himself. Maybe when he goes up the weights, not that he’ll come unstuck but I think he’ll have a little bit more to think about.”

In the aftermath, Inoue tipped his hat to Butler for taking on the challenge and coming to Japan.

“This has been a long journey for me but this is the final chapter at bantamweight and I have made it. Now I consider to change my division,” Inoue said.

Before he continued: “Thanks to Butler for coming to Japan, I could not have done this without him and I commend him. I anticipated a longer bout and I was able to show you more, so I am happy. I am satisfied with boxing longer than usual today.”