Tim Tszyu has called off his impending world title fight with Vergil Ortiz Jr on medical advice.

The Australian boxing star was due to fight the undefeated American but has been ruled out by doctors who say he is unfit to fight as he continues to recover from his brutal bloodbath against Sebastian Fundora in late March.

No Limit Boxing CEO George Rose confirmed on Friday morning that Tszyu had cancelled plans to fight Ortiz for the welterweight interim title on August 4.

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“We are bitterly disappointed with the set back and Tim is extremely frustrated after a great pre-camp with Kostya,” Rose said in a statement.

“He showed everyone that he’ll fight through anything against Fundora but this decision was taken out of his hands to be honest.

“Ultimately, it was his body and medical professionals telling him he wasn’t ready yet.”

Doctors have told Tszyu he is still six weeks away from sparring.

He was headed for a 25th-straight win in an unblemished career record after having the better of the first two rounds against Fundora before an errant elbow split his head open and caused profuse bleeding.

The face of Australian boxing was then forced to effectively fight blind for the final 10 rounds as blood gushed over his eyes.

Tszyu gallantly refused to give in but looked increasingly affected by the significant blood less before eventually going down on a split decision.

Excitement for the Tszyu-Ortiz clash had already been in overdrive after the Aussie’s two-week training camp in Thailand alongside his famous father, boxing legend Kostya Tszyu.

The younger Tszyu appeared fit and firing in multiple training videos uploaded where he and his Hall of Fame father were seen completing intense sessions together.

No Limit Boxing said details about Tszyu’s eventual return to the ring would be provided “in the future”.