PARTICK THISTLE manager Ian McCall is hoping his side's promotion push isn't derailed by their latest injury setback.

John Robertson has been ruled out with severe ligament damage for up to six weeks following an incident in the Homecoming Scottish Cup tie against Inverness and McCall is gutted at the news.

"It is a real blow for us," he said. "He has been left with severe ankle ligament damage and we are quite irked about it because we felt the challenge itself was a bad one and yet it went unpunished.

"It now means that we are looking at being without a player who has been pretty exceptional for us this season for up to six weeks, at a time when we have a lot of games that will have a big bearing on our season.

"John has been excellent and it really is disappointing that we'll be without him. He has been in inspirational form and he will definitely be missed.

"All we can do is hope that we can keep going and just try to take it game by game until he is ready to come back in.

"We aren't really in the position of being able to go into the transfer window and bring someone else in at this stage so we just need to get our heads down and get on with it.

"The trouble is that we have rarely had a time this season when we have had everyone fit and available for selection.

"And then at those times when we have been without players we have had a couple of people who play the same positions out of the team simultaneously.

"That can be hard to cope with because we don't have the biggest of squads and obviously the key is keeping players injury and suspension-free."

On a brighter note, Liam Buchanan should be fit for Saturday's game against league leaders St Johnstone after going off at the break last weekend merely as a precaution.

"Liam went off at half-time because he felt as though his groin was a little bit tight, but it was a precaution more than anything else," said McCall.

"He had played three games in a week and the tightness was just an effect of that. It was not related to the original injury he had and we think he'll be fine for the weekend's game against St Johnstone."

The Perth side were in action last night against Rangers and McCall expects them to put up a decent fight at the weekend.

However, a win for the Jags at Firhill would enable them to close the gap on the league leaders to just three points and McCall has set his sights on the victory.

"We're looking forward to it," he said. "We watched their game last night but it will be totally different to the type of game it will be on Saturday.

"It is a chance for us to move within three points of the league leaders and I don't think there's a bigger incentive than that.

"Hopefully we'll get a decent crowd on Saturday that get behind the team.

"I don't think this is an easy place for anyone to come and we want to make sure that we do everything we can to try and get the victory."

"It would be a great boost for us."