Updated

Rome, Italy (SportsNetwork.com) - French star Jo-Wilfried Tsonga and rising Bulgarian Grigor Dimitrov moved on, while 13th-seeded Italian Fabio Fognini was a first-round upset victim and 10th seed Kei Nishikori pulled out of the draw at the $4 million Italian Masters.

The 11th-seeded former top-10 star Tsonga grounded Ukrainian Alexandr Dolgopolov 6-3, 7-6 (7-5) in Monday's nightcap at Foro Italico, while the 22- year-old 12th-seeded world No. 14 Dimitrov, the youngest player in the ATP's top 20, rallied to beat France's Edouard Roger-Vasselin 4-6, 6-3, 6-4, and Czech slugger Lukas Rosol drove out Fognini in easy 6-3, 6-2 fashion.

Nishikori was Sunday's Madrid Masters runner-up to Rafael Nadal, who prevailed when the rising Japanese star retired from their championship match in the third set due to a back injury.

On Monday, Nishikori became the first-ever Japanese man to land in the top 10, but his back problem forced him to skip the Rome event. He was replaced in the draw by Colombian lucky loser Alejandro Falla.

Fourteenth-seeded Russian Mikhail Youzhny moved on Monday by dismissing Frenchman Nicolas Mahut 6-4, 6-4.

Meanwhile, former top-10 Frenchman Gilles Simon grounded Italian wild card Filippo Volandri 6-2, 6-3 and Spaniard Marcel Granollers dismissed fellow countryman Feliciano Lopez 7-5, 6-1 on Day 2. Simon is rewarded with a second- round match against the world No. 1 superstar Nadal, who captured last week's Madrid Masters and is a seven-time Rome titlist.

Nadal beat Roger Federer in last year's marquee Rome finale.

Additional wins at this clay court French Open tune-up came for Spanish qualifier Pere Riba, Croats Ivo Karlovic and Ivan Dodig, Italian wild card Simone Bolelli, and French qualifier Stephane Robert.

The second round will commence Tuesday, including matches for second-seeded Novak Djokovic and third-seeded Australian Open champ Stan Wawrinka. The Serbian star Djokovic will face Czech veteran Radek Stepanek, while the 2008 Rome runner-up Wawrinka will encounter the aforementioned Riba. The two-time Rome champion and two-time runner-up Djokovic will return to action after being sidelined for a few weeks with an arm injury.