(CNN)  -- Alberto Contador will take a 39-second lead into the final stage of the Tour de France after fighting off a determined challenge from Andy Schleck in Saturday's deciding time trial stage. Spain's Contador had an eight-second advantage going into the 52km solo test from Bordeaux to Pauillac and came under pressure from his Luxembourg rival at the early time checks. For some fleeting moments it seemed possible that Schleck could reclaim the yellow jersey, but as he tired, Contador, considered a far superior time triallist, increased his advantage. And at the finish, a relieved and tearful Contador had extended his lead by 31 seconds.
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Alberto Contador has 39-second lead going into 20th and final stage of Tour de France
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Contador extends his advantage over Andy Schleck in 52km time trial near Bordeaux
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Denis Menchov of Russia moves into third place overall ahead of Samuel Sanchez
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Schleck's Saxo Bank teammate Fabian Cancellara wins stage in fine style
Contador had gained 39 seconds on @placeholder, ironically the margin that will likely separate them at the finish in one of the closest fought Tours in recent years.