Gavin DeGraw turns to Instagram to reconnect with NYC bartender after piano bar performance

Singer-songwriter Gavin DeGraw turned to social media for help reconnecting with a New York City bartender after a memorable performance this week.

Bartender Zach Nolan said he's been singing at The Duplex, a historic piano bar in Greenwich Village, for the last five years. Almost every week, he strikes a chord performing DeGraw's song "Not Over You."

This Wednesday was far from a regular night, though; DeGraw himself showed up at the bar. Nolan said he approached the singer-songwriter to thank him for writing the song.

"Then moments later, he was like, 'Hey, do you want to sing it?' And I was like, 'Yeah, let's do it,'" Nolan said.

Video shows DeGraw playing piano while Nolan sings.

Nolan said they lost contact after hitting the stage, but Friday morning, he woke up to messages and notifications.

DeGraw had posted a video of their performance on his Instagram account with a caption reading, "Ok Instagram, do your thing. Help me find this guy. He crushed it."

"Initial state of shock, honestly. It was kinda surreal. Surreal moment," Nolan said. "Initially just kind of got nerves a little bit, too. I didn't really know what to do. I didn't know if I should reach out or whatnot. I just kinda reposted the post and just said, 'Thanks for an incredible night,' and just retagged him."

DeGraw replied to Nolan's comment on the video, saying, "You rock my brother. Keep giving that love to the world."

In a statement, DeGraw told CBS News New York: "You never know what will happen in NYC and I'm a sucker for a piano bar… Zach's got something real and I loved what I heard!  I'm glad the post found its way back to him - Looking forward to crossing paths and making some noise together again soon!"

Nolan's response?

"Listen, I'm here every Wednesday and Friday, Gavin. Come see me. I'm here for it," he said.