Jannik Sinner’s preparations for the US Open ended in emotional scenes as he retired from the Cincinnati final after just five games and 23 minutes.

Jannik Sinner and Carlos Alcaraz continue their rivalry on Monday afternoon, when they face off in the Cincinnati Open finals at 3 p.m. ET.

Jannik Sinner retired with an apparent illness 23 minutes into the first set of the Cincinnati Open final against Carlos Alcaraz.

It felt like tennis had delivered the perfect script—world No. 1 Jannik Sinner versus world No. 2 Carlos Alcaraz in a Masters 1000 final. Both had torn through the draw in Cincinnati, barely breaking a sweat, setting up the dream clash fans had been waiting for.

With just hours of rest after Monday’s Masters 1000 Cincinnati final, Carlos Alcaraz and Jannik Sinner will carry their rivalry into the mixed doubles of the US Open, which debuts a new format in the week leading up to the main draw.