Carlos Alcaraz suggested that he was 'not well mentally' after crashing out of the US Open in one of the biggest shocks in Grand Slam history. He was beaten by Botic van de Zandschulp, who produced the match of his life to secure a secure a 6-1 7-5 6-4 triumph against the odds.

Alcaraz was the heavy favourite going into the match but was unable to find his best form and was made to pay the price. He was guilty of several uncharacteristic errors, allowing his Dutch rival to dominate proceedings and claim a surprise victory in straight sets.

Speaking after the match, Alcaraz sparked concern by suggesting that his mental health was on the decline following his victories at the French Open and Wimbledon earlier this year.

"The truth is that what I feel right now is that instead of taking steps forward, I’ve taken steps back in terms of my head and I don't understand why," he said in his press conference.

"Because I came from a spectacular summer, from Roland Garros, from Wimbledon, coming out of there saying that mentally I had taken a step forward, like I had realised that to win big things or Grand Slams you had to be mentally tough. I come to this tour and it’s like I’ve taken steps back.

"It’s like I’m not well mentally. I’m not well, I’m not strong. Among the problems I have is that I don’t know how to control myself, I don’t know how to manage it and that’s a problem for me, really."

Alcaraz explained that his busy summer schedule has taken a heavy toll, with the 21-year-old also reaching the Olympic final after going all the way at Roland Garros and Wimbledon.

"I have to see what exactly happened or what exactly is happening to me," he added. "The truth is that it has been a very emotional summer, very demanding as I said. The tennis calendar is very tight, things are super tight.

"I have had my moments of disconnection. But well, I think that I am still getting to know myself and maybe as a person I need more time. I have to get to know myself."

Asked what he was planning to do next, Alcaraz replied that he would speak to his team and discuss the best course of action before taking to the court again.

"Right now I don’t want to say anything, because if I say anything, it could be completely the opposite," he said. "I don’t know. I have to talk to people close to me, to my team, to my people, and see what steps to take.

"We’ll keep going. Obviously, I have tournaments ahead of me, but, honestly, I don’t want to think about any of that."