World number one Novak Djokovic required medical attention after being struck in the head by a water bottle following his second-round win against France's Corentin Moutet at the Italian Open on Friday.

The Serbian was signing autographs after his easy 6-3 6-1 victory against the lucky loser when he was hit in the head by the bottle and he immediately clutched his head as fell to his knees. He remained crouched on the ground for several seconds as staff ran to his aid and was eventually helped off court.

Tournament organisers said there was no cause for concern over his condition.

"Novak Djokovic on leaving the Central Court at the end of his match was hit on the head by a water bottle while signing autographs (for) spectators," the tournament said in a statement posted on social media.

"He underwent appropriate medication and has already left the Foro Italico to return to his hotel."

Footage posted to social media showed the bottle had slipped out of a fan's backpack and hit him. Reuters was not immediately able to independently verify the footage.

"Thank you for the messages of concern," Djokovic wrote on the social media platform X. "This was an accident and I am fine resting at the hotel with an ice pack. See you all on Sunday."

He next plays Chilean Alejandro Tabilo.