Contador is a superior rider against the clock to the Schleck brothers, but insists he cannot bide his time until Saturday’s 42.5-kilometre penultimate day’s time-trial, with Cadel Evans (BMC Racing) also in contention.
With six days of racing and the Alps to come, the Spanish Saxo Bank-SunGard team leader lies four minutes behind yellow jersey incumbent Thomas Voeckler (Europcar), but crucially 1min 45secs behind Andy Schleck (Leopard Trek), 1:54 adrift of Evans and 2:11 behind Frank Schleck (Leopard Trek).
Speaking on the Tour’s second rest day, Contador said: “With my current position overall, I can’t win the Tour on the time-trial in Grenoble.
“There are three very important days in the Alps.
“Right now the differences are very big and the Galibier (on Thursday) is probably where the most time differences will be because it is the hardest stage.
“If I want the victory, I will have to attack and have a good rhythm from the start.
“Alpe d’Huez (on Friday) is very short, so not so good, but Pinerolo (on Wednesday) could be dangerous if the weather is bad.”
Feeling fatigued from May’s Giro d’Italia success and bruised from a crash-strewn first week of the Tour, Contador was far from his best in the Pyrenees and was unable to cut his deficit overall.
“If I had been in better shape in the Pyrenees, I would have gone for it, I would have attacked,” said Contador, who had the support of a partisan crowd which had flooded across the border from Spain.
“With the great atmosphere in the Pyrenees, with all the fans there, I’d have loved to attack.”
Contador’s participation in the race was also shrouded in doubt and he is perhaps feeling the mental strain of next month’s Court of Arbitration for Sport (CAS) hearing into his positive drugs test at last year’s Tour. He denies wrongdoing and insists clenbuterol came into his system as a result of contaminated meat.
Despite a troublesome first two weeks of the Tour, Contador is positive of an improvement as the race enters the defining climbs which will decide who stands atop the podium in Paris on Sunday.
The 28-year-old said: “I’m sure I’m going to be better in the Alps than in the Pyrenees.
“The biggest problem has been the crashes, my knee is very seriously affected.
“There’s only a week to go now, but I’m confident I will be much better in the Alps.”
Andy Schleck has finished runner-up to Contador in each of the last two years, his 2010 result coming despite lacking the support of elder brother Frank, who crashed out earlier in the race.
However, the Luxembourg siblings can now form a two-pronged attack on Contador and their other rivals.
Contador believes the situation makes life more difficult for Leopard Trek, rather than easier.
He added: “Every day that goes past without knowing which brother is the leader is harder for them.
“It’s not far to Paris and they have to think which strategy to go for.
“If they don’t attack then it’s complicated, with Voeckler and Evans too.”
Contador would not rule out Voeckler’s challenge after the Frenchman surprised even himself by holding onto the maillot jaune for a full week.
“He’s a big rival, he is a clear candidate for the win and came through the Pyrenees with flying colours,” he said.