Alcaraz lost to Frenchman Monfils 4:6, 7:6 (7:5), 6:4 in a second-round match that was postponed the previous day due to rain.

The 21-year-old Spaniard, who has won the French Open and Wimbledon this year, smashed his racket after failing to break against 37-year-old Monfils in the third set.

“Sometimes I felt like I wanted to break the racket,” said Alcaraz immediately after the defeat. “That never happened to me before because I was able to control myself in such situations, with such feelings.”

“Today I couldn’t control myself because, as I said, I felt like I wasn’t playing tennis at all.”

The Olympic silver medalist later apologized for his behavior on his official Instagram account, external and said he would work to ensure there was no repeat at the US Open, which begins on August 26.

“I would like to apologize for my behavior yesterday, it was not good and something like that should not happen on the pitch,” he wrote.

“I’m only human. My nerves are on edge and sometimes it’s very difficult to keep this tension under control.

“I will work to ensure this doesn’t happen again. Now is the time to think about NYC!”

Monfils then played against Rune and lost to the Dane 3:6, 6:3 and 6:4.

Meanwhile, world number one in women’s tennis, Iga Swiatek, made it into the quarterfinals of the Cincinnati Open with a comfortable 6-2, 6-2 win over Marta Kostyuk.

She will play against Mirra Andreeva, who defeated Italian Wimbledon finalist Jasmine Paolini 3-6, 6-3, 6-2.

“I’m glad I was solid. I was disciplined about all the things I wanted to take care of,” Swiatek said.

Aryna Sabalenka secured a 7-5, 6-2 win over Elina Svitolina, while Jessica Pegula won a delayed second-round match against Karolina Muchova 5-7, 6-4, 6-2 before defeating Taylor Townsend 6-2, 6-3 in her second match of the day.