Federer wears down Wawrinka to maintain mastery over compatriot

Tennis - Wimbledon - All England Lawn Tennis and Croquet Club, London, Britain - July 11, 2018. Switzerland's Roger Federer attends a press conference after loosing his quarter final match against South Africa's Kevin Anderson . Florian Eisele/AELTC pool via Reuters

(Reuters) - Roger Federer continued his mastery over Stan Wawrinka, but not before getting a fright en route to a 6-7(2) 7-6(6) 6-2 quarter-final victory at the Cincinnati Masters on Friday.

Federer upped his career record against his Swiss compatriot to 21-3.