The day's honours in the 184.5-km 14th stage went to France's Christophe Riblon, the last survivor of an early breakaway. But second and third place, 54 seconds behind Riblon, went to Russia's Denis Menchov and Spain's Samuel Sanchez, the two riders most likely to pose a threat to Schleck and Contador for final victory.
Luxembourg's Schleck and twice champion Contador dropped 14 seconds in the finale because neither would lead the way towards the finish line.
"If I have to play poker in the end, I'll play poker. I felt really good today but I could afford to lose time on Menchov and Sanchez. I don't consider them as Tour contenders," Schleck told reporters.
"I did not want to pass Alberto and lose seconds like in the Mende stage," Schleck said, explaining his fear of being attacked by Contador. "I had to play games today.
"I want to win this. I've got to be smart", he added.
First and second in last year's Tour, Contador and Schleck were seen playing hide and seek and almost stopping in the final ascent like sprinters waiting to surge on a cycling track.
"We were content with controlling each other and in the end we decided to work together to limit the damage with Menchov and Sanchez. We could not afford to let them take too much time," Spaniard Contador said.
It remains to be seen whether the pair's approach was the smart one as it might give ideas to their rivals in the next three stages in the Pyrenees.
"The tactic for today was to stay in Contador's wheel but tomorrow will be another day as I need to take more time off him in the future," said Schleck about Monday's 187.5-km 15th stage to Bagneres de Luchon, which looks easier on paper.
His 31 seconds edge over Contador appears a little slim ahead of the final 52-km individual time trial to Pauillac on the penultimate day of the race. The bluff had started in the hardest hill of the day, the Port de Pailheres, 30 km from the finish.
Contador's Astana team-mates led for most of the climb and Schleck went down to his team director's car to pick up bottles and signal he was not impressed by their pace.