Carlos Alcaraz appeared to lose his temper during his US Open defeat against Daniil Medvedev

Having started well, Alcaraz lost a first-set tiebreaker before tumbling through a 6-1 second-set loss.

At one point, the Spaniard appeared frustrated and was seen nearly throwing his racket to the floor.

The 20-year-old admitted that he came close to crossing the line, which would likely have earned him a warning, but managed to keep his cool.

“Well, I think I started the match pretty well. It was a close first set,” Alcaraz said.

“In the tiebreak, you know, after 3-All in the tiebreak, I, let’s say, I lose my mind. I make three or four points without control. I didn’t think. I totally lose my mind on that set, and fighting for 50 minutes and then, you know, for four points lose my mind. It was really tough for me to handle it.

“You know, in the second set I didn’t came back. It was almost in the moon (smiling). For me it was tough. Obviously Daniil, he was playing great. You know, it was tough for me to came back, you know, to the match and playing a great game again.

“You know, I almost threw the racket to floor, but I just control myself just be in the moment, but it was tough for me to stay calm.”