Barcelona coach Tito Vilanova could inflict a double blow to Celtic's Champions League hopes tonight by beating the Hoops at Parkhead.
A Barca win coupled with a Spartak defeat against Benfica would assure the Primera Liga leaders of first place in the group.
Asked what would he would do if such a scenario unfolded, Vilanova, whose side have still to travel to Moscow before finishing with a home game against Benfica, replied: "It is probably the most important match in what is left of the year. If we qualify and are first in the group we will be able to rest some of our players and use the youth team."
When challenged on that policy later, in terms of it going against the spirit of competition and thus potentially harming Celtic's qualification chances, Vilanova gave Hoops fans some succour.
"I said the game was really important so that we could qualify and give some players a rest," he said. "But do not worry, the teams that will play in the next games will always be top level. The fact that some of those players don't play often doesn't mean they don't have an excellent level."
Vilanova refused to criticise Celtic for their display in the 2-1 defeat in the Nou Camp last month, saying: "I don't know how they will play in front of their own crowd but they weren't that defensive really in the first game, they played really well.
"It was really hard for us to beat them and we could only do that in the last minute. When you play against Barcelona, they force you to defend close to your goal."