There are sure to be plenty of fireworks inside of London's O2 Arena on Sunday as all four singles and doubles semifinal matchups are set after a wild Day 6 at the 2012 ATP World Tour Finals.
In the final two Group B singles matches, Juan Martin del Potro outlasted Roger Federer in three hard-fought sets, while David Ferrer knocked off Janko Tipsarevic in the day's final match.
The results set up two intriguing singles semifinal showdowns on Day 7. Group A winner Novak Djokovic will play Group B runner-up Juan Martin del Potro, while Group B winner Roger Federer will take on Group A runner-up Andy Murray.
On the doubles side, the third-seeded pair of Leander Paes and Radek Stepanek defeated tournament favorites Bob and Mike Bryan in a three-set thriller. The other Group A doubles match saw Marcel Granollers and Marc Lopez defeat Aisam-Ul-Haq Qureshi and Jean-Julien Rojer.
Paes and Stepanek finished group play with a perfect 3-0, while Qureshi and Rojer will go home after a disappointing week, finishing 0-3 and at the bottom of Group A.
Here, we have you covered with results and recap from a thrilling Day 6 in London.
Day 6 Results
Singles - Group B
(6) Juan Martin del Potro defeats (2) Roger Federer; 7-6 (7-3), 4-6, 6-3
(4) David Ferrer defeats (8) Janko Tipsarevic; 4-6, 6-3, 6-1
Doubles - Group A
(3) Leander Paes and Radek Stepanek defeat (1) Bob Bryan and Mike Bryan; 6-4, 6-7 (6-8), 10-7
(6) Marcel Granollers and Marc Lopez defeat (7) Aisam-Ul-Haq Qureshi and Jean-Julien Rojer; 6-4, 6-2
Del Potro Stuns Federer
Former U.S. Open champion del Potro pulled off a stunner on Saturday in London, defeating world No. 2 Roger Federer in three sets to clinch a semifinal berth and end the 31-year-old legend's 12-match winning streak at the circuit finale.
The victory over Fed was del Potro's second straight over the Swiss star.
The win highlights what has been a career year for the 24-year-old Argentine. Del Potro boasts a 63-15 singles record in 2012 and can add to his win count with a strong outing in Sunday's semis and perhaps the Monday final.
Bryan Brothers Upset
American tennis stars Bob and Mike Bryan fell in a thrilling three-set match to Paes and Stepanek. The result means that the No. 1-seeded pair will head home without even escaping the group stage.
Paes and Stepanek are making their first appearance at the ATP World Tour Finals, while the Bryan brothers have won three doubles championships at this event since 2003.
The pair of Paes and Stepanek will move on to play Group A's runner-up team of Mahesh Bhupathi and Rohan Bopanna in Sunday's semifinal. Paes and Stepanek should be favored considering their opponents are every bit as inexperienced at the circuit finale.
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