Eddie Hearn, promoter for former world champion Anthony Joshua, has cautioned that his British star will have an enormous amount of pressure on him to get revenge on Andy Ruiz.

Last Saturday night, the entire sport witnessed one of the biggest upsets in boxing history when Ruiz dropped Joshua four times to secure a seventh round stoppage at Madison Square Garden in New York City.

The victory gave Ruiz the WBO, WBA, IBF, IBO world titles.

Joshua has exercised an immediate rematch clause, and the second fight will take place in the fall and likely on UK soil.

Hearn cautions that Joshua, should he lose again, would find his career in complete turmoil.

Ruiz on the other hand, will enter the fight with a lot more confidence and will look to once again check the chin of Joshua.

"There's so much pressure on the rematch, as if he loses that second fight then his career is not in a great place," said Hearn to BBC Sport.

"At the moment, he's lost his world title belts and he's got a chance to win them back. If he was to lose that second fight, it's not career-ending but it starts to make you think about your career - and that's long before we expect that moment to happen. The rematch is by no means a forgone conclusion.

"Ruiz's confidence is going to go through the roof; AJ's confidence probably isn't going to be the same. I think he was probably too overconfident. What we saw was one of the biggest heavyweight shocks of all time. But we also saw an amazing fight, and now it's down to Anthony."