Australian Cadel Evans has refused to discount Alberto Contador's bid for a fourth yellow jersey despite the Spaniard suffering from knee trouble going into key mountain stages.
Contador hampered an existing pain in his right knee during his fourth crash in eight days on Sunday's ninth stage, the second in the Massif Central.
The Spaniard, who has won all six Grand Tours in which he has competed in, finished the stage with all the yellow jersey favourites but still has a deficit of 1min 30sec to Andy Schleck and 1:41 to Evans.
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Evans has had his team to thank for keeping him safe in an injury-plagued week of racing which has ruled two other potential challengers, Jurgen van den Broeck and Bradley Wiggins, out of the equation.
After a first week that seemed more about survival, the yellow jersey race will move up a considerable notch during three consecutive stages in the Pyrenees starting Thursday.
Evans has finished runner-up twice on the race, in 2007 and 2008. The first time he lost to Contador by 23secs after his team made the tactical error of not chasing the Spaniard down on a mountain, conceding 40secs.
Asked whether he still considered ailing Contador a threat, Evans replied: "Absolutely. He's won all of the last Grand Tours he's competed in since 2007 so you cannot rule him out.
"Contador has tested us a bit, on the stage (four) to Mur de Bretagne, and I'm sure he will try to again on Luz Ardiden."
Thursday's 12th stage is the race's first mountaintop finish at Luz Ardiden, the Pyreneean climb where Lance Armstrong soared to victory in 2003 despite having crashed on the way to the summit with Iban Mayo and Jan Ullrich.
However the third week of the race is even tougher, meaning teams may try and keep their powder dry for strategic stages where they can take time from their rivals.
Evans believes the Alps, and particularly stage 19 to Alpe d'Huez, could be crucial.
"All the mountains (stage) on the Tour are hard. (In the Alps) there are some really hard days, especially that short intense day to Alpe d'Huez before the time trial.
"Everyone's going to be really tired by that point, it's going to be horrible."
Evans has suffered many injuries in his career, and admitted that if Contador's injury does not heal the Spaniard could be out.
"If he has a real knee problem, it could put him out of the race. I've seen he has a little bit of a limp when he's sitting on the bike, but that's hard to read into," he added.
Even if the injury does compromise Contador's bid, there are always the Schleck brothers Andy and Frank to contend with.
"To me in the mountains the Frank and Andy combination, other than Alberto at his best, is one of the hardest things to come up against in the Pyrenees and the Alps."
