Juan Martin del Potro makes winning return

FORMER US Open champion Juan Martin del Potro, returning from the wrist injury that sidelined him for much of 2010, beat sixth-seeded Feliciano Lopez of Spain 6-7 (5-7), 7-6 (9), 7-6 (7-3), in the first round of the Sydney International.

The Argentine saved a match point in the second set and finally prevailed on his first match point in the third-set tiebreaker, hitting a forehand to the open court.

Meanwhile, defending men's champion Marcos Baghdatis withdrew from the tournament due to a left groin injury suffered during a training session over the weekend. Other men's winners included Germany's Florian Mayer and Ukrainian Sergiy Stakhovsky.

In the women's draw, French Open champion Francesca Schiavone, of Italy, the No 5 seed, was beaten by Alisa Kleybanova of Russia 6-7 (5-7), 6-1, 6-2.

Fourth-seeded Australian Samantha Stosur advanced to the second round with a 7-5, 6-4 win over Yanina Wickmayer, of Belgium, while seventh-seeded Victoria Azarenka of Belarus beat Russian Ekaterina Makarova 2-6, 6-2, 6-4, and eighth-seeded Li Na of China defeated Anastasia Rodionova, of Australia, 6-1, 6-2.