“Like we expected, it’s a bad injury. He needs surgery on his ankle,” said Hurzeler. “I can’t say how long we expect him to be out.

“We have to look at how the rehab will go but of course it is a tough one for us.

“We will try to support him the best way we can and get him back on the pitch as fast as possible.

“Let’s hope he will be back soon.”

Crawley boss Scott Lindsey has since apologised for the tackle. He commented: “Maybe we were a bit aggressive, maybe the referee missed it (the challenge) and I would like to apologise.

“I wouldn’t want anyone to be hurt. We are both passionate about the game and we wish Brighton all the best in the next round.”

Gutted Brighton boss Fabian Hurzeler has confirmed Matt O’Riley will undergo surgery after suffering a serious ankle injury.

The former Celtic star was handed his debut less than 24 hours after completing his £30million switch from Parkhead. But he was forced off after just six minutes when he was wiped out by Crawley skipper Jay Williams’ wild tackle.

The Denmark international was unable to continue as he hobbled off the park with the help of medical staff and remarkably, referee Alex Chilowicz decided to take no action against Williams. Now, O’Riley could face months on the sidelines after Hurzeler revealed his big-money signing will go under the knife.

Speaking this morning, the German said: “Like we expected, it’s a bad injury. He needs surgery on his ankle. I can’t say how long we expect him to be out, we have to look at how rehab will go.