Paris - France's fifth seed Jo-Wilfried Tsonga defeated Stanislas Wawrinka 6-4, 7-6 (8/6), 3-6, 3-6, 6-4 on Monday to reach the French Open quarter-finals for the first time where he will face top seed Novak Djokovic.
The players had to return to Philippe Chatrier court for a second day after Sunday's action was halted because of fading light with Tsonga 4-2 up in the decider.
When they returned on Monday, Wawrinka pulled level for 4-4 but Tsonga claimed victory when Wawrinka went wide with a backhand.
Wawrinka had defeated Tsonga from two sets to love down in the third round last year.
But he had struggled early in Sunday's action, and even required extensive treatment on his back when he trailed 3-5 in the second set.
The 18th-seeded Swiss dug deep into the resources which carried him through two five-setters in the first three rounds to eventually level the tie at two sets each as the light faded.
Tsonga, however, broke for a crucial 3-1 lead in the decider and was 4-2 up when play was halted for darkness.