Baltacha reached a career-high ranking of 49 in 2010 and won 11 singles titles during her career.

Del Potro stretched his Washington win streak to 14 matches by adding to the titles he won in the US capital in 2008 and 2009.

The unseeded Indo-German pair, which had shocked top seeds, lost 4-6 6-7(1) to the Filipino-Briton combo in the second round of the USD 1,295,790 hard court tournament.

They next face Treat Huey of Philippines and Briton Dominic Inglot in the quarter-finals.

Somdev, who created a record by retaining the NCAA title beating Isner 7-6 (7), 4-6, 7-6 (2) in 2007, was overpowered in their first meeting after that collegiate final here Thursday.

Somdev got the better of American Jesse Witten with a 7-5 6-0 scoreline. Sanam Singh had disappointment in store as he lost 0-6 5-7 to Australian 12th seed Samuel Groth.

The 12th-seeded Ivanovic faced a tough challenge from her French rival in the first set but raised her game in the tiebreaker.

Top-seeded Samantha Stosur advanced to the quarterfinals of the Japan Open by beating Virginie Razzano of France 1-6, 6-2, 6-4.

Top-seeded Samantha Stosur advanced to the quarterfinals of the Japan Open by beating Virginie Razzano of France 1-6, 6-2, 6-4.

Melanie Oudin of the United States has been awarded a Wimbledon wild card after reaching the final of the grass-court Aegon Classic.