![Roger Federer of Switzerland (R) shakes hands with Swiss coach Ivo Werner during a Davis Cup tennis training session at the Pierre Mauroy stadium in Villeneuve d'Ascq, northern France, November 19, 2014. Roger Federer of Switzerland (R) shakes hands with Swiss coach Ivo Werner during a Davis Cup tennis training session at the Pierre Mauroy stadium in Villeneuve d'Ascq, northern France, November 19, 2014.](https://c8.alamy.com/comp/2CY00RG/roger-federer-of-switzerland-r-shakes-hands-with-swiss-coach-ivo-werner-during-a-davis-cup-tennis-training-session-at-the-pierre-mauroy-stadium-in-villeneuve-dascq-northern-france-november-19-2014-france-will-face-switzerland-in-their-davis-cup-final-which-will-start-on-friday-november-21-2014-reuterspascal-rossignol-france-tags-sport-tennis-2CY00RG.jpg)
Roger Federer of Switzerland (R) shakes hands with Swiss coach Ivo Werner during a Davis Cup tennis training session at the Pierre Mauroy stadium in Villeneuve d'Ascq, northern France, November 19, 2014.
Number nine seeded Martina Hingis of Switzerland returns a backhand... Nachrichtenfoto - Getty Images
![Swiss tennis player Roger Federer (R) listens to his doubles partner Tommy Haas from Germany during..., Stock Photo, Picture And Rights Managed Image. Pic. PAH-40135012 | agefotostock Swiss tennis player Roger Federer (R) listens to his doubles partner Tommy Haas from Germany during..., Stock Photo, Picture And Rights Managed Image. Pic. PAH-40135012 | agefotostock](https://previews.agefotostock.com/previewimage/medibigoff/b5000cea93cb3f22925ad86badd384a1/pah-40135012.jpg)
Swiss tennis player Roger Federer (R) listens to his doubles partner Tommy Haas from Germany during..., Stock Photo, Picture And Rights Managed Image. Pic. PAH-40135012 | agefotostock
![Roger Federer Switzerland (R) schüttelt Hände mit Robin Söderling aus Schweden gewann das Herren Finale bei den French Open Tennis-Turnier in Roland Garros in Paris 7. Juni 2009. REUTERS/Benoit Tessier (Frankreich SPORT Roger Federer Switzerland (R) schüttelt Hände mit Robin Söderling aus Schweden gewann das Herren Finale bei den French Open Tennis-Turnier in Roland Garros in Paris 7. Juni 2009. REUTERS/Benoit Tessier (Frankreich SPORT](https://c8.alamy.com/compde/2e88ta5/roger-federer-switzerland-r-schuttelt-hande-mit-robin-soderling-aus-schweden-gewann-das-herren-finale-bei-den-french-open-tennis-turnier-in-roland-garros-in-paris-7-juni-2009-reutersbenoit-tessier-frankreich-sport-tennis-2e88ta5.jpg)
Roger Federer Switzerland (R) schüttelt Hände mit Robin Söderling aus Schweden gewann das Herren Finale bei den French Open Tennis-Turnier in Roland Garros in Paris 7. Juni 2009. REUTERS/Benoit Tessier (Frankreich SPORT
![Belinda Bencic of Switzerland (back, R) celebrates as Angelique Kerber of Germany looks disappointed..., Stock Photo, Picture And Rights Managed Image. Pic. PAH-65670231 | agefotostock Belinda Bencic of Switzerland (back, R) celebrates as Angelique Kerber of Germany looks disappointed..., Stock Photo, Picture And Rights Managed Image. Pic. PAH-65670231 | agefotostock](https://previews.agefotostock.com/previewimage/medibigoff/93b07f2fe3d54cf15beb0c286cad8aec/pah-65670231.jpg)
Belinda Bencic of Switzerland (back, R) celebrates as Angelique Kerber of Germany looks disappointed..., Stock Photo, Picture And Rights Managed Image. Pic. PAH-65670231 | agefotostock
![Professional Tennis Player Belinda Bencic of Switzerland Celebrates Victory after Her 2019 US Open Quarter-final Match Redaktionelles Bild - Bild von netz, könig: 160267330 Professional Tennis Player Belinda Bencic of Switzerland Celebrates Victory after Her 2019 US Open Quarter-final Match Redaktionelles Bild - Bild von netz, könig: 160267330](https://thumbs.dreamstime.com/z/e-r-160267330.jpg)
Professional Tennis Player Belinda Bencic of Switzerland Celebrates Victory after Her 2019 US Open Quarter-final Match Redaktionelles Bild - Bild von netz, könig: 160267330
![Switzerland's Davis Cup team member Roger Federer (R) looks on as Stanislas Wawrinka warms up before a practice session in Fribourg, February 8, 2012. Switzerland will meet the U.S. in the Davis Switzerland's Davis Cup team member Roger Federer (R) looks on as Stanislas Wawrinka warms up before a practice session in Fribourg, February 8, 2012. Switzerland will meet the U.S. in the Davis](https://c8.alamy.com/comp/2CX256Y/switzerlands-davis-cup-team-member-roger-federer-r-looks-on-as-stanislas-wawrinka-warms-up-before-a-practice-session-in-fribourg-february-8-2012-switzerland-will-meet-the-us-in-the-davis-cup-tennis-tournament-on-february-10-12-reutersmichael-buholzer-switzerland-tags-sport-tennis-2CX256Y.jpg)
Switzerland's Davis Cup team member Roger Federer (R) looks on as Stanislas Wawrinka warms up before a practice session in Fribourg, February 8, 2012. Switzerland will meet the U.S. in the Davis
![Roger Federer (R) and Stanislas Wawrinka of Switzerland attend a Davis Cup tennis training session at the Pierre Mauroy stadium in Villeneuve d'Ascq, northern France, November 20, 2014. France will face Switzerland Roger Federer (R) and Stanislas Wawrinka of Switzerland attend a Davis Cup tennis training session at the Pierre Mauroy stadium in Villeneuve d'Ascq, northern France, November 20, 2014. France will face Switzerland](https://c8.alamy.com/comp/2E5P0JB/roger-federer-r-and-stanislas-wawrinka-of-switzerland-attend-a-davis-cup-tennis-training-session-at-the-pierre-mauroy-stadium-in-villeneuve-dascq-northern-france-november-20-2014-france-will-face-switzerland-in-their-davis-cup-final-which-will-start-on-friday-november-21-2014-reuterspascal-rossignol-france-tags-sport-tennis-2E5P0JB.jpg)