Roger Federer set up a French Open semi-final against defending champion Rafael Nadal by overcoming fellow Swiss Stan Wawrinka in four sets.
Shortly before Federer won, Nadal completed a 6-1 6-1 6-3 win over Kei Nishikori in the quarter-finals.
But 20-time Grand Slam champion Federer endured an energy-sapping three hours and 17 minutes on Court Suzanne Lenglen to win 7-6 (7-4) 4-6 7-6 (7-5) 6-4.
"The complete dream would be to win the tournament," said Federer, 37.
"But I'm very happy, number one, to be back in another semi-final of a Grand Slam. It hasn't happened in the last year or so. I had some tough losses in fourth rounds or quarters.