LONDON — The last to arrive, befitting his reputation in the locker room, Frances Tiafoe strutted into the post-match news conference after clinching Team World's Laver Cup victory over Roger Federer's star-studded Team Europe and shouted, "Champs are here!"

Then the 24-year-old from Maryland joined his teammates at the table where the silver trophy was resting Sunday night, put down a bottle of water, pulled a Budweiser out of his red jacket and smiled that wide smile of his.

Performing with the same infectious showmanship and crunch-time success he displayed en route to his first Grand Slam semifinal at the US Open earlier this month, Tiafoe staved off four match points and came back to beat Stefanos Tsitsipas 1-6, 7-6 (11), 10-8, giving Team World its first triumph in five editions of an event founded by Federer's management company.

"I don't like losing," said Federer, a 20-time major champion whose final match before retirement was a loss alongside Rafael Nadal in doubles against Tiafoe and Jack Sock on Friday night.

"It's not fun. It just leaves not the best taste." When Tsitsipas put a forehand into the net to end Sunday's contest — and the three-day competition — Tiafoe dropped his racket and fell to his back on the court, where teammates piled atop him.

After getting on his feet, Tiafoe cupped a hand to his ear, asking spectators for more noise, then pointed to his chest and yelled, "I'm him! I'm him!" "When it becomes a circus out here, and I'm just using the crowd and acting like a little kid and having a bunch of reactions ... I end up playing really well and I start building momentum off it," Tiafoe said.