Djokovic also struggled with his serve in a semi-final loss to Fernando Verdasco at the Monte Carlo Masters two weeks ago. Against the 28th-ranked Bellucci, he got in just 57 percent of his first attempts _ although he committed only half as many unforced errors as the Brazilian.
Djokovic is aiming to reach his third consecutive final in Rome, having won in 2008 and lost to Rafael Nadal last year.
Later, Nadal was up against No. 39 Victor Hanescu in the night match at the Foro Italico.