Christopher Meloni Surprises Mariska Hargitay as They Attend US Open with Their Spouses

Chris Meloni and Mariska Hargitay enjoyed each other's company during an evening off from filming their respective Law & Order shows.

Meloni, 60, surprised his former Special Victims Unit costar, 57, with a friendly kiss on the forehead on Friday, as he arrived in the Grey Goose box at the US Open to watch Novak Djokovic take on Alexander Zverev. Although Hargitay knew her longtime scene partner would be in attendance, she reportedly wasn't aware they'd be seated in the same box.

During the match, Hargitay sat next to husband Peter Hermann, 54, as Meloni popped up in the row behind them, arriving with his wife Sherman Williams, 61. The group cheered on Djokovic, who prevailed over Zverev, 4-6, 6-2, 6-4, 4-6, 6-2, during the semifinal at Arthur Ashe Stadium.

Hargitay and Meloni starred together in the first 12 seasons of Law & Order: SVU, from 1999 to 2011, before he left the show. Meloni opened up last month about the contract negotiations that sparked his exit.

"I was just so sad, because we started this thing and built it together," Hargitay told PEOPLE of her costar's departure in February. "And we went through so many milestones and spent so much time together and understood so many things that nobody else could understand."

The pair has carried their bond over to the recently-premiered spinoff Law & Order: Organized Crime, which is led by Meloni's Detective Elliot Stabler. Hargitay has revived her role as Captain Olivia Benson in several episodes of the first season, which brought their characters closer together than ever. The show has been renewed for a second season, which premieres September 23 on NBC.

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Meloni and Hargitay previously opened up to PEOPLE about their onscreen chemistry and reuniting in front of the camera for the crossover event that also brought Meloni back to SVU for several episodes. "It was Pavlovian: Ring that bell, and you get right into Stabler and Benson," he said in February.

"There was so much shorthand between us, which all goes back to the trust we have," Hargitay mused. "He's always made me feel like I could just jump off the ledge, the cliff, the bridge, and he would catch me, in so many ways, whether it was comedy or acting or friendship." Meloni added: "It's simple. We have each other's back."

Longtime fans of the Law & Order franchise have been on the edges of their seats over the "will-they-won't-they" storyline since SVU first premiered in 1999. "There's a world of possibility," Meloni said of the pair's future during an April chat with Organized Crime showrunner Ilene Chaiken, hosted by PEOPLE for Wolf Entertainment.

"Obviously, we recognized it when we were together on SVU," he added. "We were always kind of toying with that, leaning into that, teasing with that."