Right-back Adam Matthews and fellow wing-back Mikael Lustig are battling for fitness ahead of tomorrow's Champions League tie, while new signing Lassad Nouioui has been ruled out.

However, the No.1 is confident Neil Lennon's men can leave their Russian hosts out in the cold.

He said: "The back four is not changing a lot these days. It's something I'm getting used to now, and it honestly doesn't matter who plays.

"After the performance we put in on Saturday, we want to try and repeat that and really test Spartak.

"You don't want to concede any cheap goals, so it is important we remain really solid at the back.

"We go into every game looking to keep a clean sheet. I've been fortunate in my career before coming here to keep a lot of them, and I just want to keep that going.

"But we're going to go with a purpose, and look to score ourselves.

"With the way Kris Commons and Gary Hooper are playing, they have been different class.

"James Forrest is a terrific player on the break as well, so we're not just going to sit back – we are looking to win the game."

Matthews is rated doubtful as he recovers from the ankle injury he picked up ahead of the win over Well and travelled yesterday wearing a protective boot.

The man who started in his place at Fir Park, Lustig, had to come off towards the end of the game after he felt a recurrence of a tight hamstring that has kept him out.

Efe Ambrose had to step across from central defence for the final few minutes of the match, and the versatile Nigerian may again be asked to fill in at right-back against Spartak in tomorrow's crucial showdown.

Lennon will wait to see how Lustig is in training at the Luzhniki Stadium tonight before making any decisions on his selection, but he is is set to have to go without Matthews.

The Celtic boss said: "Adam is a doubt after rolling an ankle, so we will have to wait to see how he is."