ROME — Andy Murray lost only his fourth match of the year, upset by Argentine qualifier Juan Monaco 1-6, 6-3, 7-5 on Wednesday in his opener at the Rome Masters.

The fourth-ranked Murray easily won the first set before he began to miss several first serves and commit unforced errors, while the 58th-ranked Monaco won several points with an effective drop shot.

Murray's other losses this year came against top-ranked Rafael Nadal — twice in Masters Series events in Indian Wells, Calif., and at Monte Carlo — and to Fernando Verdasco at the Australian Open.

Monaco will next face 15th-seeded Marin Cilic after the 6-foot-6 Croatian beat Christophe Rochus of Belgium 6-0, 5-7, 6-2.

In the first round, held over from Tuesday due to rain, Richard Gasquet beat ninth-seeded Jo-Wilfried Tsonga 7-6 (2), 6-4. Tommy Robredo of Spain eliminated Philipp Kohlschreiber of Germany 6-2, 7-6 (5) and will now play defending champion Novak Djokovic.

Also, Robin Soderling of Sweden overcame a second-set lapse to beat Romanian qualifier Victor Crivoi 6-1, 7-6 (2), 6-1. Crivoi upset 14th-seeded James Blake on Monday.

Soderling will face either Nadal or local favorite Andreas Seppi of Italy. Also playing later, No. 2 Roger Federer opened against big-serving Ivo Karlovic.

With the sun out at the Foro Italico after two days of rain, something in the air got into Monaco's eye and he had to call the trainer and receive eye drops midway through the first set.

Monaco fell to the clay trying to react to a passing shot from Murray, but he got back up, wiped the dirt off his side and proceeded to break the Brit to take a 3-2 lead in the third. It appeared Murray thought a shot from Monaco was long, and he replied with a shot of his own that sailed past the baseline — handing Monaco the break.

Monaco fell to the clay again two games later when Murray hit a ball behind the Argentine, and threw his racket at the ball to no avail.

Still, the scrappy Argentine attacked more than Murray, coming to the net 27 times to Murray's 22. Monaco improved to 13-6 on clay this year, including a runner-up result in Buenos Aires, Argentina, in February.

Murray made his first clay-court semifinal appearance in his last outing in Monte Carlo, but he showed he still has some work to do before the French Open, which begins May 24. He's been working with two-time French Open finalist Alex Corretja during the clay-court season.

Murray could still move up to No. 3 in the rankings if Djokovic does not defend his title.