TORONTO - Andy Murray battled some leg pain but showed no signs of Olympic hangover as the gold medallist moved into the last 16 of the Toronto Masters while a fatigued Juan Martin del Potro was one of three seeds ousted Wednesday.
Murray, playing his first match since beating world number one Roger Federer in the gold medal match at the London Games on Sunday, called out a trainer late in a 6-1 6-3 win over Italian Flavio Cipolla, which he later attributed to a change of playing surfaces from grass to hardcourt.
The Briton, who appeared to hurt himself while chasing down a forehand, received about five minutes of massage on his left quadriceps while leading the final set 3-2 and failed to move around the court as well the rest of the way.
Still, the second seed, who is scheduled to face big-serving Canadian Milos Raonic in the third round, managed to chase down drop shots and held serve throughout the 82-minute match.
Third seed Frenchman Jo-Wilfried Tsonga became the highest seeded player to get eliminated on Wednesday as he fell 6-4 7-6 to compatriot Jeremy Chardy.
Del Potro, whose Olympic semi-final loss to Federer five days ago was the longest men's three-set match played in the professional era, admitted fatigue got the better of him during a 6-4 7-6 loss to Czech Radek Stepanek.
"It's not easy to play after a big effort in the Olympics," the sixth seeded Argentine told reporters. "Now I need time to recover my body if I want to stay healthy."
Del Potro, who was playing his first match since beating Novak Djokovic for the bronze medal at the Olympics on Sunday, also said he had no doubt he would be ready for the Aug. 27-Sept. 9 U.S. Open, where he won his sole grand slam in 2009.
In other action, fourth seed Tomas Berdych avoided a scare by rallying for a 6-7 6-4 6-4 win over Julien Benneteau in a match that lasted just over three hours, while 15th seed Florian Mayer of Germany fell 6-3 6-4 to Spain's Marcel Granollers.
Fifth seed Janko Tipsarevic of Serbia was a 7-6 6-4 winner over Russia's Mikhail Youzhny and Croatian 10th seed Marin Cilic breezed by Greece's Marcos Baghdatis 7-5 6-3.
Defending champion Djokovic is scheduled to play Australian Bernard Tomic later on Wednesday. (Reporting by Frank Pingue; Editing by Mark Lamport-Stokes)