London: Switzerland's Stan Wawrinka and Roger Federer opened their ATP Tour Finals campaign in scintillating style by beating Tomas Berdych and Milos Raonic respectively yesterday.


Stan Wawrinka celebrates after defeating Tomas Berdych at the ATP World Tour Finals tennis held at the O2 Arena yesterday and Roger Federer. Pics/Getty Images 

While Wawrinka demolished Berdych 6-1, 6-1, Federer defeated Milos Raonic 6-1, 7-6 (7/0) at the prestigious event held at London's O2 Arena.