CRAIG GORDON racked up his his third clean sheet in a week at Motherwell on Saturday.

But the Celtic keeper accepts he might be the one of the men shut out when Ronny Deila selects his side to close out their Europa League Group D games in Zagreb on Thursday.

The carefully-controlled return to full match fitness has helped the 31-year-old play 21 games already this season and recover his very best form.

But, with qualification for February's knockout round of the Europa League already secured, it would appear an ideal opportunity to give Gordon and his knee a rest.

He said: "I'm quite happy to play on Thursday, if selected. I'll have a chat with the manager during the week and see what squad he is looking to take over to Zagreb.

"If I'm not involved, it gives me a good opportunity to have a week's training where I can concentrate on building my knee up.

"I could maybe train a little bit harder than I'd do if I was having to play a game. So, there's positives in that as well for me.

"But, if I am playing, I'll go about it the same way I have done when we have been playing midweek games the rest of the time."

Gordon is learning quickly that alertness is every bit as important as agility when you play in goal for Celtic. He can have little to do for most of the match then be required to pull off one save to ensure the result is safe.

Gordon added: "That's another part of the job, really. More often than not that should be the case here. It's a different side of the game for me, but you have to make sure you are concentrating 100 per cent."