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Red-hot Rafael Nadal was an easy winner Wednesday, while birthday boy Andy Murray retired from his second-round match at the $3.475 million Italian Masters due to a back injury.

The fifth-seeded former world No. 1 Nadal rolled along with a 6-1, 6-3 spanking of Italian crowd favorite Fabio Fognini.

The Spanish superstar is riding an 11-match winning streak and seeking a third title in three events. Last week's Madrid Masters champion has played in seven finals in as many tournaments in 2013 and already piled up five titles since returning from a seven-month injury layoff in February.

The clay-court king Nadal, who is the all-time leader with 23 Masters shields, is a six-time champion in Rome and topped great rival Novak Djokovic in last year's finale. Djokovic beat Nadal in the 2011 Rome final.

Nadal's next opponent will be talented Latvian qualifier Ernests Gulbis.

The third-seeded British star Murray, who turned 26 on Wednesday, lost the first set and had just won the second against Spaniard Marcel Granollers when the U.S. Open champ decided his week was over at Foro Italico. Granollers prevailed 6-3, 6-7 (5-7) at this French Open tune-up.

"I have an issue with my lower back," Murray said. "It's been an issue for a while. I would be very surprised if I was playing in Paris. I need to make a plan as to what I do. I'll chat with the guys tonight and make a plan for the next few days then make a decision on Paris after the next five days."

Murray was a semifinalist in Rome two years ago.

Meanwhile, fourth-seeded Spanish star David Ferrer came from behind to get past fellow countryman Fernando Verdasco 5-7, 7-5, 6-3. The 2010 Rome runner- up Ferrer's third-round opponent will be German Philipp Kohlschreiber.

More seeds exited the draw when 6-foot-8 rising Pole Jerzy Janowicz recorded his third career top-10 win by dousing eighth-seeded Frenchman Jo-Wilfried Tsonga 6-4, 7-6 (7-5), Ukrainian Alexandr Dolgopolov advanced via walkover when hot Swiss and 2008 Rome finalist Stanislas Wawrinka, seeded 15th this week, pulled out of his scheduled second-rounder, citing a thigh injury, and Frenchman Jeremy Chardy dropped 16th-seeded Japanese Kei Nishikori 6-4, 6-1. A busy Wawrinka appeared in finals in his previous two events over the past two weeks, winning a championship in Portugal and finishing as a runner-up to Nadal in Madrid.

Also on Day 4 in Rome, Gulbis clobbered Serb Viktor Troicki 6-1, 6-1; Kohlschreiber erased Spaniard Albert Ramos 6-4, 6-1; Frenchman Gilles Simon handled Russian veteran Mikhail Youzhny 7-5, 6-3; and Benoit Paire outlasted fellow Frenchman Julien Benneteau 6-7 (3-7), 6-4, 7-6 (7-4). Simon's third- round opponent on Thursday will be Swiss icon Roger Federer.

Also on Thursday, the current world No. 1 star and two-time Rome champion Djokovic will face the capable Dolgopolov.