Injury worry for Thompson
By Alex Livie
Last Updated: 01/01/70 1:00am
The imperious left footer hobbled from the field of play following an innocuous challenge with Hatem Trabelsi, but O`Neill revealed the joint swelled up when he returned to the dressing room.
Former Bolton ace Thompson was sent to hospital for X-rays, with O`Neill far from confident about a swift return to action for his midfielder.
Speaking to Sky Sports, O`Neill said: "I was speaking to the doctor and he has sent him off for an X-ray.
"He could be out for some time, it has blown up substantially in the last hour or so. We will just have to wait and see."
O`Neill had more positive news on some absent players, revealing Steven Crainey, Bobo Balde and Joos Valgaeren will soon be ready for action.
"We have been playing the whole pre-season with makeshift defenders, and the return of Joos will add stability," said the former Leicester boss. "Bobo Balde is close, but not quite there yet.
"Pre-season means little, and we will be ready for Dunfermline."
O`Neill revealed there could still be additions to the squad before the transfer window closes.
He added: "We will be looking to strengthen before the first window closes."