Juan Martin del Potro had to rally to a hard-fought win over Nicolas Mahut in Sydney.
Mark Nolan/Getty Images/SI

SYDNEY (AP) -- Former U.S. Open champions Juan Martin del Potro and Samantha Stosur rallied to win their second-round matches against tough French opponents Wednesday at Australian Open warm-up tournaments.

Del Potro beat Nicolas Mahut 1-6, 6-3, 6-4 at the Sydney International, while Stosur saved two match points and eked out a 6-4, 2-6, 7-6 (7) win over Kristina Mladenovic at the Hobart International.

Stosur lost all three of her singles matches at the Hopman Cup team exhibition event last week and is looking for some confidence heading into her home Grand Slam at Melbourne Park, where she has never advanced past the fourth round.

''Any win's a good win, but when you've got to really tough it out and battle through a long match ... you're probably holding your nerve pretty well,'' Stosur said.

The Australian Open begins Monday.

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