behind. In 20th place was Fignon, arriving 11 minutes after Hinault. Roche lost 21 minutes, Phil Anderson () 33 minutes. Stage 13 led the race through the Pyrenees again, over and four high mountain passes. The first was the Col du Tourmalet, coming after , followed by the Col d'Aspin, the Col de Peyresourde, and the final climb up to the ski resort of Superbagnères. Laurent Fignon had fallen ill with a fever and did not start the stage. Shortly after the start of the stage, Dominique Arnaud () attacked. When he began the ascent of the Tourmalet, he held a lead of 13 minutes over the field. A select group of favourites crossed the summit, led by Millar, now just over 7 minutes behind Arnaud. As they began the descent, Hinault attacked again, opening a gap to his opponents. As he reached the valley, his lead was at 43 seconds. Behind him, LeMond found himself again in a situation where he was unable to chase his teammate himself, while this time, the entire team was stunned by Hinault's attack, explicitly breaking the tactics the team had agreed upon in the morning, which was to sit back and have the other teams attack them. At the summit of the Aspin, Hinault's lead had increased to two minutes and he caught up with Arnaud on the subsequent descent. However, unlike the day before, the other favourites worked together to give chase, with Millar, Herrera, and Urs Zimmermann () committed to bringing Hinault back as the group reached the climb of the Peyresourde. They made contact with him on the descent and as the group began the final climb to Superbagnères, it became clear that Hinault had overexerted himself, falling back quickly. Hampsten, who had caught up with the LeMond group, attacked during the early part of the climb to soften up the opposition for LeMond. While Herrera suffering from cramp dropped back to his team car, LeMond counter-attacked, leaving Zimmermann and Millar behind and joined his teammate at the head of the race. With Hampsten falling behind soon after, LeMond continued to the finish alone and won the stage. Hinault trailed in eleventh, 4:39 minutes behind LeMond. He therefore maintained the lead of the race overall, but now just 40 seconds ahead of second-placed LeMond. Incidentally, LeMond had gained back the exact amount of time he had lost the previous day.