The defending champ pulls out with illness, raising questions about his preparations before next Sunday’s US Open.

Carlos Alcaraz won the Cincinnati Open after top seed Jannik Sinner retired as he was feeling unwell, raising concerns about the Italian’s fitness just days before he is due to begin the defence of his US Open title in New York.

The Spanish second seed snapped the world number one’s 26-match winning streak on hardcourts when his ailing rival signalled he could no longer continue while trailing 5-0 in the first set of the final on Monday.

“This is not the way that I want to win trophies, I just have to say sorry, I can understand how you must feel now,” Alcaraz told Sinner during the presentation ceremony after capturing his third Masters 1000 crown of the season following his success in Monte Carlo and Rome.

“As I said many times, you are a true champion and I am sure from these situations, you are going to come back even stronger, as you always do. That’s what true champions do.”