Matteo Berrettini announced Tuesday that he has withdrawn from Wimbledon after testing positive for COVID-19:

"I have had flu symptoms and been isolating the last few days. Despite symptoms not being severe, I decided it was important to take another test this morning to protect the health and safety of my fellow competitors and everyone else involved in the tournament.

"I have no words to describe the extreme disappointment I feel. The dream is over for this year, but I will be back stronger. Thank you for the support."

Berrettini was the runner-up in the men's singles tournament at the All England Club last year, losing to Novak Djokovic in the final.

The 26-year-old won back-to-back tournaments, the Boss Open and Cinch Championships, in the buildup to Wimbledon. Seeded eighth, he was supposed to play Cristian Garin in the first round.

Elias Ymer replaced him in the draw. The 26-year-old Swede lost to Garin in straight sets.

Berrettini's announcement will heighten COVID-related concerns since it came after Marin Cilic had to bow out because of a positive test.

The Associated Press' Howard Fendrich shared a statement from an All England Club spokesperson regarding the health measures in place:

"We have maintained enhanced cleaning and hand sanitizing operations, and offer full medical support for anyone feeling unwell. We are following U.K. guidance around assessment and isolation of any potential infectious disease. Our player medical team also continue to wear face masks for any consultation."

The tournament was already without a few notable men's stars—including Daniil Medvedev, the No. 1 player in the world, and Andrey Rublev—because of Wimbledon's ban on athletes from Russia and Belarus.

Alexander Zverev, the No. 2 overall player, also couldn't compete after undergoing surgery for an ankle injury.