Nigerian-Briton Anthony Joshua lost his IBF, WBA, WBO heavyweight titles to Oleksandr Usyk in front of a London crowd on Saturday night.
The result sees the Ukrainian become the new unified heavyweight world champion.
Usyk put on a dominant display winning by 117-112, 116-112, 115-113 in front of 65,000 fans inside Tottenham Hotspur Stadium, outclassing Joshua over 12 rounds.
The defeat is the second in Joshua’s career after the first to Andy Ruiz last year.
Joshua was forced to fight the WBO mandatory challenger and former undisputed cruiserweight champion Usyk after his high-profile fight with fellow Briton Tyson Fury collapsed last summer.
Speaking with BBC Radio 5 Live, Joshua’s promoter Eddie Hearn suggested his fighter may have suffered a broken eye socket and would need to go to hospital.
“I don’t know if he has broken his eye socket, it doesn’t look great. He said he couldn’t see after the ninth round, obviously he was getting tagged a lot as well,” he said.
Joshua has an option to trigger a rematch to reclaim his titles.
Hearn said his fighter had given Usyk too much respect and would have to make “fundamental changes” to regain his titles.
Meanwhile, Fury fights Deontay Wilder next month in Las Vegas.