Lennox Lewis has urged Anthony Joshua to axe trainer Rob McCracken.
Joshua lost his unbeaten record and world heavyweight titles when he was shocked by Andy Ruiz Jr in New York.
McCracken has been by Joshua's side throughout his career from Olympic glory to his stunning victory over Wladimir Klitschko at Wembley and also trained Carl Froch during his impressive career.
But former world heavyweight champion Lewis believes Joshua needs to make a change, as he did when he was beaten by Oliver McCall in 1994.
"I say you can't go to university with your third grade teacher. They won't have the answers you need at that level. You need a professor by then," Lewis said.
"McCracken is A1 without question but maybe not the fit for the style AJ needs to fight
"I switched to Manny Steward who understood how to leverage all of my physical attributes and skills and showed me everything I needed to know for success.
"Aside from that AJ was not prepared for anything Ruiz brought to table."
Meanwhile, Joshua has moved to deny allegations made by Dillian Whyte over why he was beaten in New York.
“Joshua could be heard on camera asking his trainer Rob McCracken, ‘Why do I feel like this?’ after the sixth round," Whyte told his YouTube channel.
“It is because you’re in America with the VADA testing and you’re not on the juice, that’s why.
“It’s harder to get therapeutic use exemptions in America than the UK, that’s why.”
Promoter Eddie Hearn has also denied claims the Brit had suffered a panic attack going into the fight while it is unclear why his father confronted the promoter afterwards.
