Novak Djokovic has been issued a telling warning ahead of the defence of his US Open title. The Serbian icon gets his campaign at Flushing Meadows underway on Tuesday morning, with a first round match against unseeded Moldovan Radu Albot.

The second seed is aiming to win the American Grand Slam for the fifth time, which would signify an unprecedented 25th Major title of his illustrious career.

The 37-year-old was given a scare in practice this week when he was forced to cut short a session with an injury worry, but is set to be fully fit in time to take on Albot.

But now Mats Wilander, a seven time Slam winner who also tasted victory in New York in 1988, has told Djokovic has needs to be ‘careful’ in the early stages given his lack of preparation.

Djokovic finally landed the one major title to have alluded him this summer when he won Olympic gold in Paris, but his clay court focus meant he has been able to play a hard court event in the build-up to the US Open.

“Novak isn’t even playing a tournament on hard court before the US Open,” Wilander said on Eurosport. “That hasn’t happened in, I don’t know how long, especially when it’s his decision to not to.

“But the one thing that really helps when you don’t play a tournament on that same surface before a major is the focus of that player in the first few rounds. So I think Novak, he knows that he is good enough, but he also knows that he has to be careful even though it’s on his favourite surface.”

Wilander, 60, also argued that Djokovic should have arrived in American in a relaxed state of mind having finally landed the Olympic title he craved. And the Swede firmly believes the victory cemented his status as the greatest player in history.

“Obviously, it makes everyone that’s involved in the sport extremely happy,” he added. “We can now clearly say, whether it’s a woman or a man, that the person that has won 24 majors and the Olympic gold and Davis Cup, and has won the most tournaments in terms of ATP 1000, that he is easily the BOAT, the best player of all time.”

Wilander also forecast an exciting fortnight of competition in the men’s singles. Despite the success of Djokovic in Paris, it’s Carlos Alcaraz who is aiming for a third straight Grand Slam title, after beating his rival in the final at Wimbledon before also going on to capture the French Open.

“So it’s very open, which tells me that the men’s game is most probably in one of the most healthy situations that it has been since Rafa Nadal, Novak Djokovic and Andy Murray started to challenge Roger Federer,” said Wilander. “So I’m expecting an unbelievable two weeks.”

Neither player however, will go into the event as the top seed. That honour goes to Jannik Sinner, but the build-up to his tournament has been overshadowed by the controversy surrounding him avoiding a suspension for failing two doping tests at Indian Wells in March.