Novak Djokovic will aim for his record 25th Grand Slam at the US Open, but former British tennis star Andrew Castle believes that's just not possible with Carlos Alcaraz and Jannik Sinner around. Djokovic won his last Grand Slam in 2023, and even though he won a Gold at the 2024 Paris Olympics, he hasn't looked a player who can win Grand Slams in the last year. He suffered an embarrassing straight-set loss to Jannik Sinner at Wimbledon 2025, where he looked down and out physically, with slow reflexes and movement. The British legend said that Novak Djokovic has achieved some remarkable feats in tennis, but he is finished in terms of winning Grand Slams, adding that he can only pull off a win if Jannik Sinner gets injured or Carlos Alcaraz has a bad day. "It doesn’t look like much to me," Castle told Betway. "I mean, it doesn’t look like to me that if Carlos Alcaraz and Jannik Sinner are around that he could win another Grand Slam. "It looks like the perception is, he’s finished in terms of winning Grand Slams. It’s the last kind of chapter in this storied career and now we analyse what he has done. "At the French Open, I believe it was his 19th quarterfinal at the French Open alone. That is what the locker room talks about. I mean, the 24 Grand Slams is obviously ridiculous. But 19 French quarter-finals… and there’s records like that everywhere and Novak’s won everything twice or three times. He’s won every single title. "Let’s just say he’s had a good run but how do you think that he feels about it? Well, okay, wait until Sinner gets injured and Carlos has a bad day and loses, then we can have a different conversation. "But as long as those two are there, I can’t see Novak winning and it’s probably exactly what he expects people to say. Castle said that he would love it if Novak Djokovic could win the US Open, where he was dramatically disqualified in 2020 after accidentally hitting the ball in line of the judge. He continued that the veteran should retire from tennis if he wins the US Open. "I think that’s absolutely magnificent, and I would love it, I would be on my feet if he could get a run going and make it 25 Grand Slams at the US, especially the place where he was disqualified that one time," Castle added. "It would be glorious and the moment he wins the 25th, I think he should retire. You can’t go on forever, he should play as long as he wants but personally, I don’t think he is likely to win this one or another one, he added.