Jo-Wilfried Tsonga of France and Stanislas Wawrinka of Switzerland pulled off separate upset victories Tuesday. The pair advanced to the next round will play each other in the semifinals of the 2015 French Open.

Tsonga, the lowest seed among all quarterfinalists at No. 14, beat No. 5 seed Kei Nishikori of Japan in five sets, 6-1, 6-4, 4-6, 3-6, 6-3, while No. 8 seed Wawrinka defeated No. 2 seed Roger Federer, 6-4, 6-3, 7-6 (4).

Nishikori, who rose to a career-high world No. 4 ranking in recent months, was one of the players who was considered dark horse contenders in the clay court Grand Slam. However, Tsonga, who was cheered on by a wild home crowd, proved that he can beat elite players in consecutive matches. The Frenchman defeated No. 4 seed Tomas Berdych of the Czech Republic in the previous round, 6-3, 6-2, 6-7 (5), 6-3.

Meanwhile, Federer fell in anticlimactic fashion when Wawrinka defeated him in straight sets. Wawrinka was in top form all throughout the match, breaking the former No. 1’s serve three times in eight break opportunities. Federer just couldn’t get through his compatriot going 0-of-4 on break-point opportunities.

Wawrinka and Tsonga have split the six meetings they have faced each other on the court. Five of these meetings have come on clay, with the most recent match-up at the 2014 Davis Cup, where Wawrinka defeated Tsonga, 6-1, 6-3, 3-6, 6-2. The pair has also met twice in past Roland Garros tournaments and again have split their French Open match-ups. Tsonga beat Wawrinka, 6-4, 7-6, 3-6, 3-6, 6-4 in 2012 and Wawrinka defeated Tsonga, 4-6, 6-7, 7-6, 6-2, 6-3 in 2011.