Bruce Springsteen made a guest appearance at Madison Square Garden last night to help mark Billy Joel’s 100th appearance at the iconic New York venue.

“I’d like to bring out an old friend,” Joel told the crowd before Springsteen appeared. “We go back a long ways – we were both on the same record label, we both got dumped by the label. But we did it.” It was only when he called his guest a “Tony Award winner” (an honor presented by Joel last month) that most audience members figured out who they were about to see -- though some fans had been hooting "Bruce" before that.

As they started into Springsteen’s song “Tenth Avenue Freeze-Out,” Springsteen said, “I’m not wearing a guitar now,” and he later jumped onto Joel’s piano as its platform revolved. He later strapped on a guitar for “Born to Run," often encouraging the crowd to join in.

You can watch their renditions of “Tenth Avenue Freeze-Out” and “Born to Run” below.

Joel holds the record for most performances at Madison Square Garden, with his current residency due to run until December. The Boss’ Springsteen on Broadway show is also set to run until December, after which Netflix will air a special starting on Dec. 15.

Springsteen was recently asked if he was considering taking the intimate show on tour, but only replied, “We’ll see, we’ll see, we’ll see.” He also joked that, despite his working-class reputation, his residency at the Walter Kerr Theatre was the first time he’d ever worked five days a week.