WATCH: Sock works on his golf swing

WHITE SULPHUR SPRINGS, W. Va.—Players at The Greenbrier this month are playing a lot of World TeamTennis, and a lot of golf. Many Americans and Brits have been dueling it out on the greens including Jack Sock, Jonny O'Mara, Coco Vandeweghe, Ryan Harrison, Sam Querrey and more.

On Tuesday, Sock showed off his swing:

He's been competing for New York Empire, and his team is 4-4 so far. They've been having fun on Creekside Stadium—even when things don't quite go their way.

Sock gets to practice and compete alongside former No. 1 Kim Clijsters, and the honor isn't lost on him.

"She's obviously a legend of the game," he says. "Any wisdom, any knowledge, we can get from her slash having her on the bench cheering us on and playing with her hopefully in mixed a little bit would be super fun."

Sock and Clijsters made their mixed doubles debut on Wednesday against the San Diego Aviators, winning 5-2. Sock also won his singles set and doubles (with Neal Skupski), and then captured the supertiebreaker to get the 20-19 victory for New York.

For more photos, videos, results and live action from World TeamTennis, go to WTT.com.