Amir Khan was left to deny accusations he floored Zab Judah with a low blow as he clinched his light-welterweight unification fight with a fifth-round stoppage in Las Vegas.

Judah was left angered after he was counted out after he had believed he would be given time to recover from a punch he thought was below the belt.

Sections of the Mandelay Bay Events Centre were left booing as Khan was handed the victory, to ensure the Bolton fighter added the IBF world title to his own WBA belt.

"He went down. It was above the belt," Khan said in an interview aired on Radio Five Live.

"It was nowhere near below (the belt). It was a great shot.

"Zab's a great fighter. I respect him a lot."

Judah did not agree with his rival's assessment, claiming: "Everyone in world who saw the fight will see that's a low blow.

"I thought he (the referee) was giving me time to get up.

"He then said 'over'. I thought he was giving me a standing eight-count. I didn't understand that."