"Every goal they scored was cheap." That was the verdict of the Dundee United defender Jim Lauchlan on Celtic's 5-1 demolition of United in Glasgow on Saturday.

It was a scoreline that meant Celtic continued to average over 2.5 goals per game in the Scottish Premier League. In their brief history in the Champions League it is less than half that: four games, four goals. But even that average would prove acceptable tonight if Celtic's one was a winner.

With Rosenborg cut adrift at the bottom of Group E, the other three clubs, Juventus, Porto, and Celtic are squashed together at the top. Celtic know that if they win their match against the Norwegian side in the Lerkendal Stadium this evening then another victory, over Juventus at Parkhead next Wednesday, would guarantee Martin O'Neill's men second phase Champions League football.

It may yet not come to that, a draw and a win from the last two games may prove enough. But given that Celtic have yet to win away in the group, were humiliated last week in Portugal and that Juventus are unbeaten away from Turin, O'Neill will want to collect three points in Trondheim.

Celtic can hope that with Rosenborg trying to sew up a 10th Norwegian title in 10 years - they are one point ahead of Lillestrom with one game left but lost at home on Saturday - that Rosenborg's thoughts will be trained on participating in next season's Champions League rather than remaining in this year's competition.

There would be a measure of wishful thinking in that, though. While they were beaten 2-1 by Porto here in the group opener, Nils Arne Eggen's side held Juventus 1-1 after that. They also drew with Bayern Munich in the Lerkendal Stadium last season.

As O'Neill sat in the Lerkendal with temperatures dropping last night he was under no elusions as to the scale of the job required over the next eight days. "We are working on the assumption that we have to win both games," he said.

But he believes his side perform better under pressure and is backing them to produce the result when they most need it.

He also had some team news to boost him. Henrik Larsson not only travelled but trained having been taken off on Saturday. Similarly, Chris Sutton also travelled and trained having missed Celtic's last three matches.

ROSENBORG (probable): Arason; Olsen, Stensas, Hoftun, Saarinen; Strand, Skammelsrud, Berg; Rushfeldt, George, Brattbakk.

CELTIC (probable): Douglas; Balde, Valgaeren, Mjallby; Agathe, Lennon, Lambert, Petrov, Thompson; Sutton, Larsson.