ATP Finals: Federer, Sock advance to semifinals

Roger Federer dominating at the ATP Finals is nothing new.

The Swiss star beat Marin Cilic 6-7(5) 6-4 6-1 to finish a perfect 3-0 at the conclusion of round-robin play – the 10th time he’s gone undefeated at this stage in 15 visits to the ATP Finals.

Federer broke late in the second set after a wild backhand error from Cilic and cruised from that point, utterly dominating the third and clinching victory when Cilic played a running forehand into the bottom of the net.

“I played really well so I’m happy to be playing this level right now,” Federer said.

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Jack Sock’s emergence, however, has been more of a surprise.

The American qualified for the tournament at the 11th hour thanks to his victory at the Paris Masters, and continued his momentum on Thursday in London.

His 6-4 1-6 6-4 win over third-ranked Alexander Zverev ensured he finished second in his group with a 2-1 record, and he now joins Federer in the semifinals.

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“I didn’t expect to be in London in the first place. To be here was a good achievement given the way my second half of the year was going,” Sock admitted.

“Paris was a big step for me. Now to put myself in the position to play on the weekend is another big step forward, another confidence booster.

“Some hard-fought matches the last few days. Just fortunate to get through.”

Sock went down a break immediately in the third set and received a point penalty for belting a ball into the stands, but recovered to build a 4-1 lead. He lost that, but steadied once again to run out a winner in just under two hours.

Zverev (with a 1-2 record) and Cilic (0-3) are out of the tournament.

Sock will go on to play Grigor Dimitrov in the semifinals, while Federer’s opponent will be the winner of the match between Dominic Thiem and David Goffin, scheduled for Friday at The O2.

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“Both great guys, good friends of mine on the tour,” Federer said.

“I’ll watch that one tomorrow, try to relax now and then one more weekend, one more push, before the vacation and then the preparation for next season.”