The summer signing from Celtic only signed for Brighton on Monday and was handed his debut on Tuesday night in the Carabao Cup against Crawley Town.
Just nine minutes into his first appearance for the club he was on the wrong end of a heavy challenge from Crawley captain Jay Williams and had to be taken off as a result.
The £25m new arrival will now face an operation, with Brighton boss Fabian Hurzeler unsure of when he will be back in action.
‘It’s like we expected, a bad injury,’ said the German at a press conference on Thursday. ‘He needs surgery on his ankle.
‘I can’t say how long we expect him to be out, we have to look how the rehab will go. But of course it’s a tough one for us, we try to support him the best way we can.We try to get him as fast as possible back on the pitch and let’s hope he will be back soon.
‘I had a small chat with him yesterday, it’s not the best situation, he’s very disappointed but he’s a good character, a very positive guy and looks immediately in the future. He says he’ll be back soon and come back stronger and that’s a very positive thing.’
It is a disastrous start to life with his new club for the Denmark international, who would have loved to have made a good impression against the League One side and then be making his Premier League debut this weekend against Arsenal at the Emirates.
Instead he is facing a lengthy spell on the sidelines, while Brighton will look to continue their impressive start to the season without him.
The Seagulls have won all three of their games under Hurzeler so far, beating Everton and Manchester United in the Premier League before downing Crawley 4-0 on Tuesday night at the Amex.
Speaking after the 2-1 win over the Red Devils, which came courtesy of an injury time winner from Joao Pedro, Hurzeler said: ‘It was emotional. It always is when you get a win in the last minute and my team deserved to win.
‘It is difficult to describe emotions. That is why I love the job. You can’t buy these emotions and you won’t get them from anywhere else.
‘But we have to be honest, if United score it would be very difficult for us. I am realistic, never euphoric, because if you are euphoric it means you lose the focus on the realistic things.’
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