Before the pros take over the USTA Billie Jean King National Tennis Center in Queens for the U.S. Open, it belongs to the fans.

Through Sunday, both casual and passionate fans of the game can enjoy access to the grounds and mostly free events leading up to tournament play next week.

Nicole Kankam, the United States Tennis Association’s managing director of marketing, coordinates the week’s worth of events.

"Every day we'll have players appearing, doing fun stuff like playing ping pong, maybe even some karaoke,” Kankam said. “But it's a great festival-like atmosphere, and it's all for free.”

The biggest draw of Fan Week is the access.

All week long, the public can get front-row seats, watching the biggest stars in the game gear up for next week's matches during open practice.

Qualifying rounds are also underway, giving 16 men and 16 women a shot to secure spots in the main draw — and fans can watch courtside.

"There's no other event where you get this kind of access to the top players in the world,” Kankam said. “You can get up close and personal to see them preparing for this greatest Grand Slam tournament."

Some events are ticketed, but the week's highlights include Wednesday's “Stars of the Open,” a tennis exhibition featuring some of the biggest names in the game, with all ticket proceeds going to supporting Ukrainian relief efforts.

“Flavors of the Open,” an event sampling food from top chefs around the world, is Thursday. “Sounds of the Open” is Friday, with a free concert on the main stage.

And Saturday is “Kids Day,” where the youngest fans will take over the grounds with a variety of different tennis activities.

Gates open daily at 10 a.m. Visit the U.S. Open’s website and register for a free Fan Access Pass to gain entrance to the grounds.