Novak Djokovic and Aryna Sabalenka have "dream double date" with wife Jelena, boyfriend Georgios

The four best friends that anyone could have! Aryna Sabalenka can't stop gushing about the "dream double date" she and boyfriend Georgios Frangulis recently had with Novak Djokovic and his wife, Jelena.

As evidenced by a post to Sabalenka's Instagram account on Thursday, the couples recently linked up for a night out in Athens, where Sabalenka again spent time after winning the US Open for a second time and where the Djokovics have recently taken up residence.

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But their recent Grecian escapade wasn't all play for the two Grand Slam champions: In addition to going out on the town with their beaus, they had a joint training session at the private Tatoi Club to prepare for their first post-US Open tournaments. Djokovic returned to the court for the first time since a New York semifinal loss to Carlos Alcaraz on Friday at the Rolex Shanghai Masters, defeating Marin Cilic, while Sabalenka is set to return at the Dongfeng Voyah Wuhan Open which begins Oct. 6.

The content reaffirmed just how much that Djokovic and Sabalenka have developed a close bond both on and off the court as they've each chased tennis' biggest prizes.

But the 24-time Grand Slam singles champion has also become tight with Frangulis, the founder and CEO of the smoothie company Oakberry. The two are joint investors in the French football club Le Mans, along with motorsport stars Felipe Massa and Kevin Magnussen.

“Novak has been an idol of mine forever, long before we became friends. I always admired him for his achievements,” Frangulis said in an interview after they became business partners.

“I love being around Novak and learning from him. And I think it’s good for him, too. He’s been on a tennis court his whole life, so exploring new areas is exciting for him. He’s a great listener, very curious about business, politics, everything. That’s why any conversation with him is always engaging and fun.”