![London, UK. 14th November, 2016. Barclays ATP World Tour Finals 02 Arena London UK Stan Wawrinka SUI v Kei Nishikori JPN who won the match in straight sets Wawrinka in action during London, UK. 14th November, 2016. Barclays ATP World Tour Finals 02 Arena London UK Stan Wawrinka SUI v Kei Nishikori JPN who won the match in straight sets Wawrinka in action during](https://c8.alamy.com/comp/H8KJ68/london-uk-14th-november-2016-barclays-atp-world-tour-finals-02-arena-H8KJ68.jpg)
London, UK. 14th November, 2016. Barclays ATP World Tour Finals 02 Arena London UK Stan Wawrinka SUI v Kei Nishikori JPN who won the match in straight sets Wawrinka in action during
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Roger Federer edges past Kei Nishikori in tense thriller at O2 Arena as he heads into last four of ATP World Tour Finals | Daily Mail Online
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Kei Nishikori fires warning to Andy Murray by crushing US Open champ Stan Wawrinka at the O2 | The Sun
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Kei Nishikori, of Japan, returns a shot, during his match against Stan Wawrinka, of Switzerland, during the Madrid Open tennis tournament, in Madrid, Spain, Thursday, May 9, 2019. (AP Photo/Andrea Comas Stock
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Kei Nishikori fires warning to Andy Murray by crushing US Open champ Stan Wawrinka at the O2 | The Sun
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ATP World Tour Finals 2015: Roger Federer eliminates Kei Nishikori as Swiss maintains 100 per cent record
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