Another all-Swiss showdown between Roger Federer and Stan Wawrinka is set for Tuesday at Roland Garros. Kei Nishikori and Jo-Wilfried Tsonga are also battling for a semifinal spot.

(8) Stan Wawrinka vs. (2) Roger Federer

Federer and Wawrinka will be squaring off for the 19th time in their careers when they clash in the French Open quarterfinals on Tuesday. The head-to-head series stands at a dominant 16-2 in favor of Federer, but it is a more even 4-2 on clay. Wawrinka’s wins have both come in Monte-Carlo; 6-4, 7-5 in 2009 and 4-6, 7-6(5), 6-2 in last season’s title match. Federer, however, restored order to the proceedings in their three most recent matches. The 33-year-old Swiss prevailed 3-6, 7-6(5), 6-4, 6-4 in the Wimbledon quarters, survived a 4-6, 7-5, 7-6(6) thriller at the World Tour Finals, and coasted 6-4, 6-2 earlier this spring in Rome.

Neither man has been severely…