Stan Wawrinka plays his fourth round match at the French Open

Stan Wawrinka of Switzerland reacts after a shot during his French Open men's fourth round match against Viktor Troicki of Serbia at Roland Garros in Paris on May 29, 2016. Wawrinka defeated Troicki 7-6 (5), 6-7 (7), 6-3, 6-2 to advance to the quarterfinals. Photo by David Silpa/UPI