Celtic midfielder Alan Thompson has admitted the timing of his latest injury is extremely frustrating.

Thompson has been ruled out of action for about eight weeks after suffering ligament damage to his left ankle against Ajax.

Thompson lasted only a few minutes of Wednesday night's friendly, which Celtic lost 3-1.

"It's frustrating when you've just done a pre-season and you're trying to get back your match fitness," the midfielder told Celtic's official website.

"It basically means I'll be facing another pre-season on my own in six weeks' time or whatever.

"I've lost my place in the team before because of spells out injured or suspended so I know it will be difficult to get back in.

"I'll have some hard work ahead of me, but I'll need to just get on with it once I'm in a position to do so."

Manager Martin O'Neill already has a number of other players on the injured list.

But O'Neill expects to have defender Joos Valgaeren back in the team to play Parma on Saturday.

Stephen Crainey is also preparing to return to training while Bobo Balde has started some running work.

Celtic are optimistic all three will be fully fit for the opening game of the season against Dunfermline.