Casper Ruud's sister and cousin have their star turn courtesy of United Cup cameras

They've got the moves. Casper Ruud's sister and cousin were thrust into the spotlight on Sunday in Sydney at the United Cup—and it wasn't just because he helped his team secure a crucial group-stage win over Croatia.

Backstage cameras at Ken Rosewall Arena caught the two strutting their stuff in the stadium hallway, only to stop and descend into a fit of giggles when they realized they were being recorded.

Meanwhile, on court, Ruud helped keep Norway alive in the competition by contributing two points for a 2-1 win over Croatia in Group F. He beat Borna Coric 6-4, 6-1 in men's singles—after Donna Vekic beat Marlene Helgo in three sets—to send the tie to a decisive mixed encounter, which Norway won thanks to a 6-2, 3-6, [10-7] victory for Ruud and Ulrikke Eikeri.

But afterwards, he couldn't help but have some playful fun at Charlotte and Josefine's expense. Ruud revealed that both women will attend U.S. colleges next fall, and that they were soaking up what might be one of their last visits to Australia—at least for a while.

"They're not typically too shy in front of the camera. They like to be around the tournaments and show up, like to sit in the box. That's their favorite thing to do. They were courtside with us," he said.

"This is not typical for them to do these things. I think they were a bit embarrassed. I saw them. They were blushing and all red in their faces.

"It was good kind of learning experience for them to say that they can't do anything they want at all times."

Norway now awaits the outcome of the last Group F match between Croatia and the Netherlands to determine if they'll have a shot at advancing into the knockout rounds. But if the result goes in the Norwegians' favor, you can be sure there will be more dancing for the Ruud clan in the not-so-distant future.