ATP Finals | Roger Federer beats Jack Sock; Alexander Zverev stuns Marin Cilic

The six-time champion was making his 15 appearance at the season-ending tournament and started positively losing just four points behind his first serve as he came through without a breakpoint. 25-year-old Jack Sock never really looked threatening especially after dropping his opening service, however, he did make amends for it by clinging on to the competition in the second set before eventually bowing down to pressure.

The 36-year-old served out the opener after 36 minutes but couldn’t succeed in closing it out in the second as five break points slipped by across the seventh, ninth and 11th games. It was for the first time in four meetings that the American has managed to take Federer to a tie-break. However, the 19-time Grand Slam champion eventually emerged victorious after a double fault from Sock at 4-5 handed him a match point, which was clinically converted.    

The second round-robin match of the Boris Becker Group, where Alexander Zverev defeated Marin Cilic 4-6 6-3 6-4 in a high-intensity game. The German third seed broke serve in the opening game with a stunning volley that gifted him the first set, however, the Croatian fifth seed wasn’t one to give up and he improved with every game, looking set for victory at 3-1 up in the decider.   

Zverev, however, showed terrific consistency thereafter winning five of the six games before breaking serve to love and take home the game. The German now faces Federer in the next game while Cilic will take on Sock.