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Roger Federer's ATP Finals tilt takes a big hit after straight sets loss Federer's ATP Finals tilt takes a big hit after straight sets loss

Roger Federer will have to do it the hard way to win his 100th career singles title after he was beaten by Kei Nishikori in his opening match at the ATP Finals.

Shock defeat hands Roger Federer an unwanted first

Kei Nishikori has defeated the Swiss world No.3 6-4 (7-4) 6-3 in one hour and 27 minutes.

LONDON (AP) — Kei Nishikori hit a backhand so good it threw Roger Federer off his game as the 20-time Grand Slam champion earned a code violation before capitulating in a surprise defeat at the ATP Finals on Sunday. Two points away from losing the opening set and on the back foot in a rally, Nishikori hit a stunning shot up the line, which prompted Federer to hit the ball into the crowd and receive a warning for ball abuse. Federer never appeared to regain his composure and went down 7-6 (4), 6-3 in a first opening match defeat at the season-ending tournament since 2013.

Roger Federer was handed the Sunday night prime time slot for the opening match of his 16th ATP Finals but fluffed his lines in an error-strewn 7-6(4) 6-3 defeat by Kei Nishikori.

Roger Federer pays for an error-strewn performance as his opening group match at the ATP Finals ends in defeat by Kei Nishikori.

Tennis: Federer loses ATP Finals opener to Nishikori Tennis: Federer loses ATP Finals opener to Nishikori

LONDON (AP) -- Roger Federer lost his opening match at the ATP Finals for the first time since 2013 as he went down 7-6 (4), 6-3 to Kei Nishikori on S

Roger Federer’s bid for 100th singles title stalls at ATP Finals Roger Federer’s bid for 100th singles title stalls at ATP Finals

The 37-year-old Swiss star was beaten in straight sets by the Japanese world number nine.

Roger Federer lost his opening match at the ATP Finals for the first time since 2013 as he went down 7-6 (4), 6-3 to Kei Nishikori on Sunday.

Roger Federer will have to do it the hard way if he is to win a record-extending seventh crown at the ATP Finals after an error-strewn 7-6(4) 6-3 defeat by Kei Nishikori on Sunday.

Kevin Anderson marks ATP Finals debut with victory over Dominic Thiem Kevin Anderson marks ATP Finals debut with victory over Dominic Thiem

The South African won 6-3 7-6 (12/10) in an hour and 47 minutes.

Kevin Anderson off to a flyer at ATP Finals with win over Dominic Thiem Anderson defeats Thiem to open ATP Finals

Kevin Anderson made a winning debut at the ATP Finals with a 6-3, 7-6(10) victory over Austrian Dominic Thiem in the opening singles match at the O2 Arena on Sunday.