World No. 1 Jannik Sinner is back in action in defense of his Cincinnati Open men’s singles title, battling Terence Atmane in Saturday’s semifinal round.

At the Cincinnati Open, the spotlight has mostly been on the usual heavyweights—Jannik Sinner and Carlos Alcaraz both cruising past opponents with ease. But this year’s story has an unexpected twist, with a new name forcing his way into the conversation.