Djokovic, who was seeded third and received a first-round bye, was playing his first match since limping out of his Australian Open semi-final in January.

It was only Berrettini's second win this year and his first over a player in the top 10 since 2023.

It was also the Italian's first ever win over Djokovic. Their previous encounters included victories for the Serb in the Wimbledon final and Roland Garros quarterfinals both in 2021.

"Something I've been looking to do for a long time. I've played against him in the most important tournaments on tour," the 28-year-old Italian said on court after the victory. "I wish I could have won one of those matches,"

Berrettini has struggled with injuries over the last 18 months but won three tournaments after returning to court last year.

"Really happy with my performance," he said. "Really happy because I enjoyed my time out there, which is the most important thing."

The first set went with serve but Berrettini took two points off Djokovic's serve to win the tiebreak.

The Italian then broke to love in the second game of the second set. Djokovic had broken Berrettini 27 times in their four previous encounters but the Italian was comfortable on serve until the final game before finally winning on his second match point.

"A champion like Novak is always ready to come back," Berrettini said. "You don't have to think about match point. You have to think about the next point, and that's what I did."

Earlier in the day, Djokovic said that Andy Murray would continue as his coach "indefinitely".

"I expressed my desire to continue the collaboration with him so I am really glad he did accept," said Djokovic.

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