ROME (Reuters) - Grigor Dimitrov opened his Rome Masters campaign with a 6-3 7-6(4) victory over Poland's Jerzy Janowicz on Monday.
The Bulgarian world number 11, beaten by Rafa Nadal in the quarter-finals in Madrid last week, earned the only service break of the match to edge into the second round where he will face home favorite Fabio Fognini.
Other seeded winners included American number 16 John Isner, who beat Portugal's Joao Sousa 7-5 6-3 and French 12th seed Gilles Simon, a 4-6 7-6(2) 6-3 winner over Jack Sock.
Big-serving South African Kevin Anderson also reached the second round, although he was stretched to the limit by Germany's Florian Mayer, winning in a deciding set tiebreak.
World number one Novak Djokovic tops the draw which also includes nine-times French Open champion Nadal, Roger Federer and Madrid Masters champion Andy Murray.
In the women's event, early losers included Australian Samantha Stosur who was beaten 6-4 7-5 by Anastasia Pavlyuchenkova.
The Russian will face top seed and defending champion Serena Williams in the second round.
Former world number one Venus Williams showed that she could still make her experience count as the 34-year-old thumped Czech teenager Katerina Siniakova 6-2 6-2.
Reporting by Martyn Herman, editing by Ed Osmond