Tottenham goalkeeper Hugo Lloris suffered a dislocated elbow during their Premier League defeat to Brighton.
The Spurs captain sustained the injury as he landed after dropping the ball on the goal line after only three minutes – a mistake that gave Brighton their first goal in a 3-0 win.
A club statement said: "We can confirm that Hugo Lloris sustained a dislocated elbow during today's match against Brighton.
"Our club captain was stretchered off as a result of the injury and will now return to London this evening after being assessed at a local hospital.
"Assessment will continue this coming week to ascertain the full extent of the injury and the length of time he will require to undergo rehabilitation."
Spurs boss Mauricio Pochettino had already been fearing the worst even before the news was confirmed.
Lloris required a lengthy period of treatment before the Frenchman was carried off on a stretcher with gas and air and was seen screaming in pain when going down the tunnel.
Speaking shortly after the final whistle at the Amex Stadium, the Argentinian said: "The news is not good from the hospital, but we need to wait.
"Everyone saw on the pitch when he landed, it was not a good situation and the news is not so good."
The incident preceded a horror show from Spurs, where they put in one of their worst displays under Pochettino, and a double from Aaron Connolly made it an afternoon to forget on the south coast.
Pochettino felt that Lloris' injury happening so early in the game affected his side.
"Of course, we cannot lie," he said. "To concede after three minutes in the way we did and what happened to our captain, it is normal that the impact was massive for the team.
"It is an emotional game and the team was very affected, we never can be in the game.
"We did not show our real performance. I am never going to take the credit away from Brighton, we need to give them the credit too, the team suffered a massive impact after three minutes.
"In the second half we tried to find a different way to play to find a solution. We started the second half well but we didn't score. You need to be lucky to score and be in the game.
"At 3-0 everyone saw the game was over and there is nothing to do after. I feel sorry for our fans. I want to say thank you for the massive effort coming here, we know how they feel, very disappointed. Everybody feels really bad, the players and staff are the same.
"We need to find a way to stay together and be all together again and find a good dynamic."