A feisty Novak Djokovic moved into the quarter-finals of the Internazionali d'Italia by seeing off Roberto Bautista Agut in straight sets on Thursday.

The 12-time grand slam champion will face Juan Martin del Potro or Kei Nishikori in the last eight after beating the Spaniard 6-4 6-4 at the Foro Italico.

There were more encouraging signs from Djokovic ahead of the French Open as the second seed stayed in the hunt for only his second title of the year.

And there was fire in the Serbian's belly, as he swore at the chair umpire after being broken in the second set, having been given a time violation.

Djokovic has endured a disappointing year and recently parted company with his long-time coaching staff, but the Serbian appeared to have rediscovered some drive and broke three times to advance under blue skies in Rome.

Bautista Agut claimed his first win over Djokovic at the sixth attempt in the Shanghai Masters last October, but there was to be no repeat in the Eternal City.

Djokovic was moving around the court more freely than he has been for much of this season, breaking to lead 4-3 when Bautista Agut netted a backhand and wrapping up the opening set after saving a first break point in the next game.

Bautista Agut made a fight of it after going 3-1 down in the second, winning three games in a row to get his nose in front, with Djokovic venting his fury at the chair umpire for being ticked off over the amount of time it was taking him to serve.

Djokovic put the blame on a ball boy before channelling his frustration to secure a win that was sealed with a sublime forehand winner.