![World number one player Andy Roddick (R) of the U.S. listens with compatriot Andre Agassi (L) and Roger Federer (C) from Switzerland to questions during a media conference in Melbourne January 13, World number one player Andy Roddick (R) of the U.S. listens with compatriot Andre Agassi (L) and Roger Federer (C) from Switzerland to questions during a media conference in Melbourne January 13,](https://c8.alamy.com/comp/2D4JK31/world-number-one-player-andy-roddick-r-of-the-us-listens-with-compatriot-andre-agassi-l-and-roger-federer-c-from-switzerland-to-questions-during-a-media-conference-in-melbourne-january-13-2004-roddick-says-doping-is-not-a-problem-in-tennis-even-though-britains-greg-rusedski-and-mariano-puerta-of-argentina-have-recently-tested-positive-for-banned-drugs-i-know-the-players-who-i-play-with-are-clean-roddick-told-reporters-as-he-prepared-for-the-kooyong-classic-exhibition-event-which-begins-here-on-wednesday-reutersdavid-gray-dgcp-2D4JK31.jpg)
World number one player Andy Roddick (R) of the U.S. listens with compatriot Andre Agassi (L) and Roger Federer (C) from Switzerland to questions during a media conference in Melbourne January 13,
Mariano Puerta of Argentina hits a backhand return to number seven... Nachrichtenfoto - Getty Images
![Argentine tennis player Mariano Puerta celebrates after winning his match against Argentine Franco Squillari in the Mexican Open, February 26, in Mexico City. Puerta won 6-4 6-1. HR Stock Photo - Alamy Argentine tennis player Mariano Puerta celebrates after winning his match against Argentine Franco Squillari in the Mexican Open, February 26, in Mexico City. Puerta won 6-4 6-1. HR Stock Photo - Alamy](https://c8.alamy.com/comp/2D59KR4/argentine-tennis-player-mariano-puerta-celebrates-after-winning-his-match-against-argentine-franco-squillari-in-the-mexican-open-february-26-in-mexico-city-puerta-won-6-4-6-1-hr-2D59KR4.jpg)
Argentine tennis player Mariano Puerta celebrates after winning his match against Argentine Franco Squillari in the Mexican Open, February 26, in Mexico City. Puerta won 6-4 6-1. HR Stock Photo - Alamy
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French Open 2018 tennis: Rafael Nadal reaches 11th Roland Garros final | London Evening Standard | Evening Standard
![Switzerland's Stanislas Wawrinka returns a backhand to [Argentina's Mariano Puerta] during their match in the third round of the French Open tennis tournament at the Roland Garros stadium May 28, 2005 Stock Switzerland's Stanislas Wawrinka returns a backhand to [Argentina's Mariano Puerta] during their match in the third round of the French Open tennis tournament at the Roland Garros stadium May 28, 2005 Stock](https://c8.alamy.com/comp/2D4GT2P/switzerlands-stanislas-wawrinka-returns-a-backhand-to-argentinas-mariano-puerta-during-their-match-in-the-third-round-of-the-french-open-tennis-tournament-at-the-roland-garros-stadium-may-28-2005-2D4GT2P.jpg)