With the tie poised at 1-1 after last month's Parkhead meeting, Celtic will again be weakened by injuries and suspensions with Marc Rieper (ankle) and banned duo Craig Burley and Tom Boyd already out.

But crucially they will have Larsson, the Swedish international who seems to have taken the burden off Jozef Venglos' off-form team for much of this season.

Defeat at Kilmarnock over the weekend leaves Celtic in some domestic turmoil, but Larsson refuses to accept morale will be anything other than high enough to do the job required.

"Everyone was disappointed we lost to Kilmarnock, but it was only a case of them taking their chances when we were never able to," he said.

"But I don't feel there is a lack of confidence. I can only speak for myself, but I sense it is also a question of luck as well and we have not had that recently."

Larsson feels it is important to view European action in its own right, but stresses he would never consider overseas glory as more significant than achievements on the home front.

"Europe is important but for us the league is important also," he said.

"They are two different competitions, I just hope though we can play better than we have been."

Stubbs hopeful

Norwegian international Vidar Riseth is ineligible for the tie which could well see Phil O'Donnell, who impressed as a substitute at Kilmarnock, offered a starting place.

But it is unclear whether Alan Stubbs will join him.

Celtic coach Venglos refused to risk the defender at Rugby Park but may well be tempted to gamble on the defender's groin injury at the Stadium Letzigrund.

Stubbs himself is cautiously optimistic about his chances of appearing.

He said: "I would say it is not 100% certain I'm going to play, I will give it every chance, but I won't really know until tomorrow morning.

"My recovery from this groin problem has been quite slow and I would have expected to be back before now only for it to take a bit longer to heal, but I'm desperate to play."

FC Zurich coach Raimondo Ponte promised a positive approach from his side as he conceded the tie is far from won despite a vital away strike a fortnight ago.

He said: "I felt 1-1 was a good result for us, but it leaves us with the decision whether to defend or attack. I still think we'll need a goal though so we won't sit back."