The two-time world champion was floored several times on the way to only a second career loss by knockout, as the IBF heavyweight title holder scored a fifth-round win.

While hopes of an undisputed bout with Oleksandr Usyk or Tyson Fury are gone, Joshua could still fight one of several other heavyweights circling below the top of the division.

But Barker, who was covering the fight for DAZN, sees only a pair of straightforward paths for the Briton if he is to solidify his legacy after a tough defeat.

"For Anthony Joshua, it's one of two options for me," he said. "It's retirement or rematch. He's chasing heavyweight history.

"He wants to be a three-time world champion and the fastest way to do it is go straight to the rematch. Does he want to rebuild? I don't think so.

"It's either he hangs up the gloves, which I don't think he's going to do, or activate the rematch clause and try and make that fight early next year."

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