On Sunday, U2 will play a giant football stadium in South Philadelphia on their Joshua Tree 2017 tour. (Read more about the band's biggest selling album, and their date at Lincoln Financial Field here.)

In 1987, the Irish rockers also played a giant football stadium in South Philadelphia on their original Joshua Tree tour. That concert was at JFK Stadium, positioned where the Wells Fargo Center now stands, across the street from the Linc.

On that tour, the band typically played Ben E. King's 1961 hit "Stand By Me" as an encore, and before doing the song at JFK, Bono asked, "Would anyone else like to play my guitar? Would Bruce Springsteen like to play my guitar?"

The Boss then emerges, and the crowd (which can't be seen in the close-shot clip below) greets him with considerable enthusiasm. "I guess you guys know him," Bono quips. "Is he a local boy or something."

Why is Bono's arm in a sling? He dislocated his shoulder at a show in Washington, D.C. a few days before. This was the second of two Philly shows in September 1987. Strangely, the band also played the much smaller Spectrum two weeks earlier.

As pointed out by John Vettese at The Key, the grainy black and white video is an outtake from Rattle & Hum, director Phil Anjou's 1988 documentary, which shares a name with the band's part-live part-studio album that came out that same year.

Watch the clip, which looks bad but sounds good, below.