Stefanos Tsitsipas regrets using sleep aid melatonin before Roland Garros loss to Carlos Alcaraz

WATCH: Carlos Alcaraz defeats Stefanos Tsitsipas in the 2023 Roland Garros quarterfinals

PARIS (AP) — Professional tennis players: They're just like you and me. Sometimes they take melatonin to try to get some Z's.

In the case of Stefanos Tsitsipas, he thought the sleep aid might have left him too drowsy on the court at Roland Garros on Tuesday night.

Tsitsipas, a 24-year-old from Greece, offered up an unusual explanation for his performance during a 6-2, 6-1, 7-6 (5) loss Carlos Alcaraz in the quarterfinals of the Grand Slam tournament.

The contest began at about 8:30 p.m. local time and lasted a little more than two hours. Tsitsipas apparently wanted to snooze a bit beforehand.

"One thing that I'm going to try to avoid in the future is (having) melatonin pills and naps before matches," Tsitsipas said, "because it clearly doesn't seem to be working."

Melatonin is a hormone that helps control the body's sleep cycle.

"Schedule has been a little bit difficult the last few days," Tsitsipas said. "I had some late-night sessions. Not super late, but late enough for me to kind of have my sleep schedule ruined, in a way."

"Sleep is a very vital, important thing, and recovery is the most important thing when competing and playing big Slams like this."

He said he also tried to take melatonin before playing against Novak Djokovic in a 2019 match at an indoor tournament in Paris. The result of that one? A 6-1, 6-2 loss for Tsitsipas.