The Eagles were joined by one of their longtime collaborators, J.D. Souther, at two of their recent concerts in Los Angeles.

Souther appeared alongside the band at the Kia Forum in L.A. on Friday and Saturday evening to perform a couple of hits he co-wrote with the group, "Best of My Love," "New Kid in Town" and "Heartache Tonight."

You can view footage of Souther and the Eagles performing "Heartache Tonight" below.

A Brief History of J.D. Souther and the Eagles

Not long after he moved to Los Angeles in the late '60s, Souther met Glenn Frey, and the two became not only roommates but musical collaborators. The duo released one album together, the eponymous Longbranch Pennywhistle, and occasionally performed live together, too.

Souther continued on with a solo career, but he also wrote music for a host of others along the way. Apart from the Eagles, he also wrote for Bonnie Raitt, Linda Ronstadt, Christopher Cross and James Taylor.

READ MORE: The Best Song From Every Eagles Album

Though he was briefly invited in, Souther never became a full time member of the Eagles – and he liked it that way.

"I think I was in the band for one day," he recalled in a 2020 interview with Acoustic Storm. "And, to be frank, they didn't need me. They were a perfectly well-rounded, self-contained band. I figured we were going to keep writing together anyway, so I think we all got the best of that situation, the best possible outcome."

Eagles Albums Ranked

The Eagles have been rightly praised for their canny combining of Glenn Frey’s city-slicker R&B with Don Henley’s country-fried rockabilly. But which LP goes this distance?

Gallery Credit: Nick DeRiso

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