Leonardo DiCaprio Rooted for Denis Istomin at U.S. Open!

Leonardo DiCaprio bites onto his headphones while going for a ride around town on a CitiBike on Wednesday afternoon (September 4) in New York City.

The 38-year-old actor attended the 2013 U.S. Open the evening before with his girlfriend Toni Garrn and friend Lukas Haas to watch Serena Williams and Andy Murray play tennis.

While it has been reported that Leo was “bored” during the evening, guests who sat near him tell us that was far from the case.

“When Uzbek player Denis Istomin was playing Andy Murray and won the first set, Leo and his friends loved that the underdog was beating the favorite and decided to root for him for the rest of the match,” a source tells JustJared.com. “They were having a lot of fun following the game, but had to leave during the second set.”

FYI: Leo is wearing Carrera sunglasses.

10+ pictures inside of Leonardo DiCaprio riding his bike around town…