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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 makes statement of intent against Stan Wawrinka at the ATP World Tour Finals | Tennis News | Sky Sports
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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
Stan Wawrinka vs Kei Nishikori in a five-set marathon! | US Open 2014 Quarterfinal | In 2014, Kei Nishikori became the first Japanese man to reach the semifinals of the US Open
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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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Stan Wawrinka, Kei Nishikori, David Ferrer and Aljaz Bedene in Rome Masters action | Tennis News | Sky Sports
![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 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](https://l450v.alamy.com/450v/2mk0hp5/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-photoandrea-comas-2mk0hp5.jpg)
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
![Rotterdam Open: Stan Wawrinka stuns top seed Kei Nishikori in three sets to enter final against Gael Monfils-Sports News , Firstpost Rotterdam Open: Stan Wawrinka stuns top seed Kei Nishikori in three sets to enter final against Gael Monfils-Sports News , Firstpost](https://images.firstpost.com/wp-content/uploads/2019/02/Stan-Wawrinka-Social-AP.jpg)