Roger Federer opened his quest for a seventh ATP Finals triumph with a confident dismissal of debutant Jack Sock at London’s O2 Arena on Sunday.

The Swiss world No 2 was happy to be back at the end-of-season showpiece for the 15th time in his career after missing out last year during a long lay-off.

And Federer made a strong start to the Boris Becker group also containing former US Open winner Marin Cilic and 20-year-old Alexander Zverev with a 6-4 7-6 (7-4) victory in 92 minutes.

Federer, at the grand old age of 36, has been keeping himself fresh after a season that had exceeded his expectations, and missed last week’s Paris Masters having secured his eighth Basel title in order to prepare for London.

Sock, who completed a week to remember in the French capital, winning his first Masters title and qualifying for the ATP Finals for the first time, made a very shaky start and was broken with a series of flashy winners by the 19-time Grand Slam champion.

The American No 1 soon settled into the contest, but Federer was moving exquisitely and wrapped up the set in 36 minutes.

Sock was slowly building up his confidence and momentum with genuine hope that he could possibly turn the match around in a hugely competitive second set.

The 25-year-old was forced to save four break points as he wriggled out of a couple of service games to force a tiebreak.

Federer picked a good time to earn a mini-break at 3-2 by catching Sock moving across his baseline. But Sock hit back, but then double faulted at a crucial time to allow Federer to serve out the match for his 50th victory of 2017.

Third seed Zverev of Germany plays Cilic of Croatia in the second group match on Sunday evening. The top two in each group qualify for Saturday’s semi-finals.

Shot of the match

Fed up and running

It was really just a matter of trying to keep the ball in play, Federer said during his courtside interview with Annabel Croft. The ball was flying, so after a while it was important to hit some good shots and play at a high intensity. I’m happy to have gone through. It feels wonderful to be back – I love playing at The O2. I can’t wait for my next match on Tuesday.

Experts’ Verdict

What’s next…

Federer plays Zverev on Tuesday knowing victory will put him in a very strong position to go through while Sock knows he must beat Cilic to have any chance of progressing to the last four.

The season-ending extravaganza ATP Finals at London’s O2 in November ends another memorable year which will be covered via our website with live blogs and updates as the season reaches its climax.

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(c) Sky News 2017: Roger Federer defeats Jack Sock in opening match at ATP Finals in London