Alexander Zverev remains confident he will become a grand slam champion despite his heartbreaking five-set loss to Dominic Thiem in Sunday’s US Open final.

The 23-year-old German was in tears during his runner-up speech on court after he blew a two-sets-to-love lead in the championship match, as well as a 5-3 advantage in the decider.

“I was super close to being a grand slam champion. I was a few games away, maybe a few points away,” said Zverev, who was contesting his first career major final.

“For me what upset me the most is not the third set or something like that, it’s the fifth set. I had a lot of chances in the fifth set and didn’t use them.

“I’m 23 years old. I don’t think it’s my last chance. I do believe that I will be a grand slam champion at some point.”

Zverev had a perfect start to the match, serving huge and dictating play. But his serve speed decreased dramatically towards the end of the final and he revealed there were physical issues behind his slow serving in the tiebreak.

“I was cramping in the tiebreaker really. My left quad was cramping, I couldn’t push off anymore. I couldn’t actually hit the first serve anymore,” explained the fifth seed, who was looking to become the first German man to win a major since Boris Becker in 1996.

Zverev cried as he paid tribute to his parents, who couldn’t travel with him to New York because they tested positive for coronavirus prior to their departure.

“They’re fine. They’re actually negative already. That’s the reason they didn’t come here,” said Zverev, whose father Alexander Sr. has been his coach all his life.

“Losing 7-6 in the fifth after being two sets to love and a break up is not easy. At the speech, I got emotional. I couldn’t put two words together. I don’t actually remember what I said. Yeah, it was a difficult moment for me,” he added.