Evans leads Schleck by just 20 seconds after Schleck won the hardest stage so far on Sunday - a grueling Alpine trek where Lance Armstrong cracked.
Speaking on Monday's rest day, Evans says "getting the yellow jersey at the Tour is always something special" and, with two-time Tour winner Contador short of his best form, Evans may never have a better chance.
Contador trails by 61 seconds ahead of Tuesday's ninth stage: A punishing Alpine route featuring two category 1 climbs, and a tougher one that is beyond classification.