ATP No. 1 Jannik Sinner retired just 23 minutes into the Cincinnati Open men's singles final, allowing Carlos Alcaraz to win the Rookwood Cup.

Carlos Alcaraz won the Cincinnati Open title in anticlimactic circumstances as rival Jannik Sinner retired due to illness just 23 minutes into the match.

Carlos Alcaraz won the Cincinnati Open title in a little over 20 minutes Monday afternoon, after his nearest rival and world No. 1 Jannik Sinner retired through illness down 5-0. Sinner fought back tears as he was forced to quit the match, which was poised to be another instalment in the most compelling current rivalry in tennis.