Carl Froch says that Anthony Joshua answered questions about his chin in his victory over Dillian Whyte.
While the 26-year-old would go on to claim the British and Commonwealth titles after knocking out Whyte with an uppercut in round seven, he was wobbled by a big left hand in the second round.
He survived that scare to triumph and record the 15th win of his career, and Froch believes the victory proved that Joshua can take a punch as well as he can dish it out.
"For the first time in Anthony Joshua's career we saw him chin checked," Froch told Sky Sports News HQ. "He got caught with a left hook on the chin that wobbled him, hurt him.
"He got hit with a very, very hard left hook, flush on the chin when he was coming forward, so he moved into it.
"What I learned from that was firstly he's human and secondly that he can take a punch. He can adapt and showed that he can recover.
"Dillian Whyte was unbeaten, came in with lots of ambition, beat Joshua as an amateur. He came in confident with that little mental edge.
"Joshua came through that, got caught with that left hook and recovered, and got the stoppage finish."
Froch is now convinced that Joshua has genuine world champion credentials.
"He's showed me there he's got the ingredients you need to become a world champion," said the retired former IBF and WBA super-middleweight champ.
"Everybody is blowing the Anthony Joshua trumpet, that he's going to be a world champion – me as well – and that solidified my opinion that he will be a world champion one day.
"He's not quite ready for it yet. You don't need to run before you can walk. He needs to defend that British title if he can, take his time, and then when he gets to world level and wins a world title, which I believe he will, then he can remain dominant for many years."