Citroen's Sebastien Loeb must beat Finnish rival Marcus Gronholm in Ireland this weekend to revive his hopes of a fourth successive world rally championship.
The Frenchman starts the penultimate round of a knife-edge season four points adrift of the Ford driver, who is retiring next month, despite having won seven rallies so far to Gronholm's five.
Should Loeb fail to score points for the fourth time this season, Gronholm will need to finish only second in Sligo on Sunday to clinch his own third title.
The odds are that the battle will go down to the wire in the muddy Welsh forests in the final Rally of Britain next month but Loeb knows he has his work cut out in Ireland's world championship debut.
He cannot afford another mistake like the one in Japan three weeks ago where he crashed out after Gronholm had already retired from the event.
'The overall result in Japan leaves us in the same situation we have been in for some events now,' he said in a team preview. 'We've absolutely got to win.
Before, we needed to win five rallies, now we need to win the next two.'
'We're still very much in with a shout, but we have very little room for manoeuvre,' said Loeb.
The event, the third new rally on the 2007 calendar, straddles north and south with a total of 20 stages over the three days.
Ford need score only three points to defend their manufacturers' title since they lead Citroen by 34 points with 36 still to be won.
'I'm really excited about the end of the season,' said Gronholm. 'Fighting for world titles in both the drivers' and manufacturers' series is a great position to be in and to win both would be the most fantastic way to end my career.
'Of course, it's not that easy and things change quickly in this sport so nobody in the team is taking anything for granted,' he added.
Essentially an asphalt rally, the winding roads pose a real challenge with plenty of bumps and farmyard mud adding to hazards in the wet.
Gronholm's team mate and compatriot Mikko Hirvonen won in Japan and competed in the Cork international rally in September to get a flavour of what he faces this weekend.
'After what I saw there, I think this will be the most difficult rally of the season,' he said. 'Nobody knows what the weather will do. It could be cold overnight so a combination of ice and narrow, bumpy roads would be extremely difficult.'
The rally starts with a super-special stage in Belfast on Thursday night.
