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Roger Federer holds the key to unlocking Alexander Zverev potential - Kiefer | Tennis | Sport | Express.co.uk
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Roger Federer can break Jimmy Connors' mark of 109 titles, says Nicolas Kiefer | Tennis News | Sky Sports
![Tennis - Australian Open - Melbourne Park - 27/1/06 Nicolas Kiefer (Germany) celebrates winning the second set Mandatory Credit: Action Images / Jason O'Brien Livepic Stock Photo - Alamy Tennis - Australian Open - Melbourne Park - 27/1/06 Nicolas Kiefer (Germany) celebrates winning the second set Mandatory Credit: Action Images / Jason O'Brien Livepic Stock Photo - Alamy](https://c8.alamy.com/comp/2EC253Y/tennis-australian-open-melbourne-park-27106-nicolas-kiefer-germany-celebrates-winning-the-second-set-mandatory-credit-action-images-jason-obrien-livepic-2EC253Y.jpg)
Tennis - Australian Open - Melbourne Park - 27/1/06 Nicolas Kiefer (Germany) celebrates winning the second set Mandatory Credit: Action Images / Jason O'Brien Livepic Stock Photo - Alamy
![Germany's Nicolas Kiefer celebrates after winning the ATP tennis tournament in Halle June 13. Kiefer won the final match against Nicklas Kulti of Sweden 6-3 6-2. JS Stock Photo - Alamy Germany's Nicolas Kiefer celebrates after winning the ATP tennis tournament in Halle June 13. Kiefer won the final match against Nicklas Kulti of Sweden 6-3 6-2. JS Stock Photo - Alamy](https://c8.alamy.com/comp/2D581RN/germanys-nicolas-kiefer-celebrates-after-winning-the-atp-tennis-tournament-in-halle-june-13-kiefer-won-the-final-match-against-nicklas-kulti-of-sweden-6-3-6-2-js-2D581RN.jpg)
Germany's Nicolas Kiefer celebrates after winning the ATP tennis tournament in Halle June 13. Kiefer won the final match against Nicklas Kulti of Sweden 6-3 6-2. JS Stock Photo - Alamy
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German tennis player Nicolas Kiefer returns the ball to French player Cedric pioline during his match at the ABN Amro World Tennis Tournament in Rotterdam February 18. FEE Stock Photo - Alamy
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German tennis pro Nicolas Kiefer looks frustrated during his match against Belarusian Mirnyi at the ATP German Masters in Hamburg, Germany, Wednesday, 17 May 2006. Kiefer lost the match in two sets
![Nicolas Kiefer, Germany, playing a backhand, tennis, the ITF Grand Slam tournament, French Open 2009, Stock Photo, Picture And Rights Managed Image. Pic. IBR-1186941 | agefotostock Nicolas Kiefer, Germany, playing a backhand, tennis, the ITF Grand Slam tournament, French Open 2009, Stock Photo, Picture And Rights Managed Image. Pic. IBR-1186941 | agefotostock](https://previews.agefotostock.com/previewimage/medibigoff/0fd978c8fe70bbffe541609013da583a/ibr-1186941.jpg)
Nicolas Kiefer, Germany, playing a backhand, tennis, the ITF Grand Slam tournament, French Open 2009, Stock Photo, Picture And Rights Managed Image. Pic. IBR-1186941 | agefotostock
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