Guimard's most striking Tour de France was in 1972, when he wore the yellow jersey as leader of the general classification and matched Eddy Merckx in the mountains. Fighting to keep the lead on long climbs created pain in his knees, one of which he injured in 1969 in an accident with a car while he was training. Merckx won two stages in the Alps and Guimard the next. Merckx tried to dispose of him on a 28 km stage to Mont Revard but Guimard, instead of cracking, won by 10 cm as the Belgian raised his hands thinking he had won.