The Empire edged the expansion Smash 21-20, with the title decided in a super tiebreaker.
With the match in extended play at 20-20 and at 6-all in the best-of-13 super tiebreaker, Vandeweghe ripped Sloane Stephens' serve with a forehand down the line that nicked the baseline.
"I've never been under that kind of pressure, ever," Vandeweghe said." It was so much fun to be on my racket to control the situation. Luckily, I controlled it in the right way. It really accentuated what World TeamTennis is -- the team vibe, team energy, people picking each other up when they're down. I had so much fun out there."
In women's singles, 2017 U.S. Open winner Stephens beat Vandeweghe 5-3 to make the score 16-13.
The Empire jumped out to a quick start thanks to Jack Sock, who had wins in mixed doubles with Vandeweghe and men's doubles with Neal Skupski. Sock fell to 18-year-old Brandon Nakashima 5-0 in singles.