Juan Martin del Potro advanced to the second round of the French Open despite discomfort in his left knee, beating Albert Montanes 6-2, 6-7 (5), 6-2, 6-1 Sunday.

The 2009 U.S. Open champion played with tape on his knee early in the match. The ninth-seeded Del Potro then added wrapping after a massage from a trainer following the second set.

Del Potro reached the semifinals at Roland Garros in 2009, but lost to eventual champion Roger Federer in five sets. A few months later, the Argentine defeated Federer in the U.S. Open final.