New Delhi, Sept. 4 -- When a fan tried to grab Jannik Sinner's bag after a U.S. Open match, the defending champion wasn't just worried about losing some of his tennis equipment.

"I checked straightaway if he took something, because I don't have only rackets there," Sinner said Wednesday night after returning to the semifinals at Flushing Meadows. "I have my phone. I have my wallet."

It was following his previous victory, in the fourth round on Monday night, that a fan attempted to open Sinner's bag when the 24-year-old went over to the stands to give away a towel and pose for a photograph. A member of the security staff quickly stopped the fan, and Sinner walked away from the crowd.

Sinner said he'd never had something like that happen...