Argentina's Juan Martin del Potro rolled into the fourth round of the French Open with an impressive 6-3, 7-6 (9-7), 6-1 victory Friday over Croatia's Marin Cilic.

Showing no visible signs of pain in his bothersome left knee, which was once again heavily wrapped, Del Potro defeated Cilic for the fourth time this year - each time in straight sets - and seventh time in nine contests.

The Argentine hit more winners than unforced errors - 31 to 28 - and only lost his serve on one occasion to advance to the round of 16 at Roland Garros for the second time in his career.

The six-foot, six-inch world No. 9's best result at this Grand Slam event came in 2009, when he reached the semifinals and lost in five sets to eventual winner Roger Federer.

The Argentine won his lone Grand Slam title that same year at the U.S. Open, getting revenge on the Swiss great in the final.

Next up for Del Potro on Sunday will be fellow big hitter, Czech Tomas Berdych, who had to battle back from a two-set-to-one deficit to edge South Africa's Kevin Anderson 6-4, 3-6, 6-7 (4-7), 6-4, 6-4.

In other action Friday, Spain's Fernando Verdasco, the No. 14 seed, was upset by Italy's Andreas Seppi, losing 7-5, 3-6, 6-3, 4-6, 6-2.

The French Open is the second Grand Slam tournament on the tennis calendar and the only one of the four played on clay. EFE