Stan Wawrinka of Switzerland plays a shot in 1/4 final match during DIEMAXTRA Sofia Open 2018 on February 09, 2018, at Arena Armeec Hall in the Bulgarian capital of Sofia. Stan Wawrinka win over Victor Troicki of Serbia 61 / 76(3) Sofia, Bulgaria on February 09, 2018 (Photo by Hristo Rusev/NurPhoto via Getty Images)
