Juan Martin del Potro has insisted that he needs to recover his physical health following an early exit from the Rogers Cup in Toronto.

The Argentine, who recently took part in the longest match in Olympic history with Roger Federer on his way to a bronze medal, lost in straight sets to Radek Stepanek on Wednesday.

"It's not easy to play after a big effort in the Olympics," the sixth seed told reporters. "Now I need time to recover my body if I want to stay healthy."

Following the defeat, Del Potro pulled out of his doubles commitments with Stepanek at the tournament in order to return to Argentina.