Vincenzo Nibali has won the 18th stage of the Tour de France, emphatically stamping his dominance on the race in its last mountain leg with a solo breakaway on the day's last climb.

After setting off from Pau, riders tackled the famed Tourmalet pass — the highest Pyrenean peak on the Tour — before heading up to Hautacam ski station at the end of the 145.5-kilometer (90-mile) leg. Both climbs are among the toughest in professional cycling.

The Italian, winning his fourth stage of the Tour, essentially turned the race into a competition for second.

Alejandro Valverde of Spain, who began the day in second but with a thin lead on two Frenchmen behind him, was losing key seconds.

The race's last big challenge is Saturday's time trial.

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