U2 closed out their concert series at Madison Square Garden last night with a special guest. Rock 'n' roll legend Bruce Springsteen joined Bono, The Edge, Adam Clayton, and Larry Mullen on stage for two songs.

"The Boss" arrived on stage with an acoustic guitar and performed “I Still Haven’t Found What I’m Looking For" followed by a unique cover of "Stand By Me," Entertainment Weekly reported.

Bono dropped a few hints to the crowd that Springsteen would in fact be joining them for the final night. Bono sang a bar of "Hungry Heart," a Springsteen classic, and an additional mic stand was brought out after they played "Where the Streets Have No Name."

Springsteen joins a long list of celebrities guest stars that have made an appearance on the Innocence and Experience tour. Lady Gaga, Jimmy Fallon and the Roots, and Paul Simon have all taken part in this U2 run.

As previously reported The Innocence and Experience Tour has featured a variety of surprises, including bringing a cover band on stage to perform with them and having fans in the audience join the band on stage.

Image courtesy of Jennifer Graylock/INFphoto.com