Stage 17 – Bagneres-de-Luchon to Peyragudes, 143.5km
However the Team Sky duo of Wiggins and Froome put him under real pressure on the final climb up to the ski station finish as they dramatically cut into his lead and distanced all their remaining rivals in the process, including third-placed Vincenzo Nibali (Liquigas-Cannondale).
Froome crossed the line in second, just 19 seconds behind Valverde, with Wiggins right on his wheel in third. Nibali was 18 seconds further back in seventh.
It all means Wiggins, who is bidding to be the first British winner of the yellow jersey in Paris on Sunday, retains a lead of 2:05 over Froome and 2:41 over Nibali, with no other rider within five minutes of the maillot jaune.
Sean Yates, Team Sky Sports Director:
“It worked out perfectly. It was up to Liquigas today as they wanted to win the stage and they rode accordingly. Valverde hung on and did a great ride but ultimately Nibali cracked and didn’t have what it took to go for that stage.
“The plan was to stick together and at the end of the stage we managed to put time into all our rivals once again. It was a great team performance.
“We still have three stages to go and you can’t switch off until you hit the finish line on the Champs-Elysees. We’ll remain vigilant and keep riding just as we’ve done up until now.”