![Switzerland's Roger Federer celebrates winning the second set against Argentina's Juan Martin Del Potro during their ATP World Tour Finals tennis match at the 02 Arena in London November 26, 2009. REUTERS/Dylan Switzerland's Roger Federer celebrates winning the second set against Argentina's Juan Martin Del Potro during their ATP World Tour Finals tennis match at the 02 Arena in London November 26, 2009. REUTERS/Dylan](https://c8.alamy.com/comp/2E790CK/switzerlands-roger-federer-celebrates-winning-the-second-set-against-argentinas-juan-martin-del-potro-during-their-atp-world-tour-finals-tennis-match-at-the-02-arena-in-london-november-26-2009-reutersdylan-martinez-britain-sport-tennis-2E790CK.jpg)
Switzerland's Roger Federer celebrates winning the second set against Argentina's Juan Martin Del Potro during their ATP World Tour Finals tennis match at the 02 Arena in London November 26, 2009. REUTERS/Dylan
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2009 Promotional photo for the ATP World Tour Finals. Back left to right: Juan Martin Del Potro (Argentina), Novak Djoko… | Jugadores de tenis, Roger federer, Tenis
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