Citroen's Sebastien Loeb believes that the new tyre rules could handicap him and his bid to win the drivers' title for the fifth year in succession.
Loeb will go into the new season, which gets underway later on this month with the Rallye Monte Carlo, as the undisputed favourite, however the Frenchman isn't taking anything for granted and reckons that with everyone having had to switch from BFGoodrich to Pirelli tyres, it is difficult to say just how things will turn out.
Indeed not only will competitors have to use tyres supplied by a different manufacturer in 2008, but they will also have to get use to having less compounds available, as well as running without any anti-deflation devices and without being able to 'modify' the rubber by making cuts.
"It is not easy to say [how I will do in 2008], because the championship next year will be different," he told French newspaper L'Equipe
according to his personal website.
"We will have to deal with a big unknown factor with a single tyre manufacturer. We will carry out tests and try and adapt the car to the new tyres, but we do not know how they will behave in the rallies. It will be advisable to be wary.
"The younger drivers will progress too - and our rivals will also have very competitive cars."
As for what he has left to prove in the WRC, especially considering he has won 36 events - something no other driver has managed, as well as having taken four drivers' titles, something only managed by two other pilots, namely Tommi Makinen and Juha Kankkunen, he noted that there are still a few things on his 'to do' list.
"I still have some challenges to meet and not least, up to now, I never have been able to win in Finland and on the Wales Rally GB," he explained.
"Also if I obtain a fifth world title I will be the only one to have managed it [in the history of the World Rally Championship]."