Martin O'Neill presented Celtic with a gloomy scenario yesterday, and it had nothing to do with any putative move by him to Tottenham Hotspur or anywhere else south of Hadrian's Wall.

Many may perceive O'Neill to be sitting in Glasgow calculating his next managerial post, but he was focused on Lyon and the threat the French champions bring with them to Parkhead tonight in the Champions League.

Preparing to field a defence shredded by injuries and against a team adept at "picking you off", he said it is imperative that Celtic do not lose. Having watched Roy Makaay score twice in the last 15 minutes in Munich a fortnight ago to take the three points - while Lyon overcame Anderlecht - a second Celtic defeat would leave prospects of progress from the group looking slimmer than slender.

That would then surely have an impact on his desire to continue working without cash at Celtic. "We can't let Lyon go six points clear," said O'Neill. "It's not the end of the world if we don't get three points, but we need to get something. When the draw was made two of the first three matches were away from home. We've already lost one, so we need to start putting points on the board."

Bayern Munich will be expected to beat Anderlecht in Brussels and, coupled with a Lyon victory in Glasgow, that would leave the group lopsided - Bayern and Lyon on six points, Celtic and Anderlecht on none. The 10 points O'Neill reckons "guarantees" qualification would not just be daunting from there on in, it might not be enough.

Given the joy created by last season's UEFA Cup campaign, Celtic would not be in tatters about trying to finish third in the group and reverting to the UEFA Cup again, but it would provide another reason for O'Neill to leave Celtic.

Last weekend O'Neill added some leverage when he spoke of the break-up of his side due to the strict economies at Celtic.

"At some stage or another all the high earners will in the next couple of years either leave, because their contracts are finished, or leave because there might be some offer that both them and the club find acceptable," he said.

"If you don't replace some of those really fine players that we have at this club with another set of fine players, then you will have to accept the consequences."

Those consequences can be seen already to some extent. With Johan Mjallby, Joos Valgaeren, Ulrik Laursen and Stephen Crainey injured, Celtic's back three tonight will feature one regular, Bobo Balde. Jackie McNamara, a converted midfielder, will start on the left, with Stanislav Varga in the centre.

They will be faced by a Lyon team that is on the move. Saturday's 4-0 hammering of Lens lifted them to third. Juninho and Eric Carriere are in outstanding form in the midfield and the attack is ably led by Giovane Elber, signed from Bayern Munich in the close season.

"They are in fine form," said O'Neill, "and it is going to be tough. They can pick you off - their main weapon is counter-attacking - so we need to be careful when charging forward. But we will have to go for it. I can't think of a single European game when we haven't gone for it."

The memory of the last Champions League matches at Celtic Park, when Juventus, Rosenborg and Porto were all defeated, should act as inspiration.

So should the implications of defeat.

Guardian Service

CELTIC (Probable): Hedman; McNamara, Balde, Varga; Thompson, Agathe, Lennon, Petrov, Sutton; Hartson, Larsson

LYON: Coupet; Deflandre, Edmilson, Mueller, Reveillere; Essien, Diarra, Juninho, Carriere; Govou, Elber.

Referee: E Iturralde Gonzalez (Spain)