It's nice to have a friend you can count on in a pinch.

Red House Painters and Sun Kil Moon's Mark Kozelek took to the stage to help out best bud and Death Cab for Cutie frontman Ben Gibbard during a solo concert last night (Feb. 23) at San Francisco's Swedish American Music Hall.

Kozelek filled in on the guitar during the show, including playing on the Postal Service song "Such Great Heights." A fan in the audience caught a frustratingly short bit of the performance and posted it to Instagram:

Another fan caught the entire performance of the new Death Cab tune, "Black Sun":

(The two recently made their friendship super official by posting a long email conversation online that they've been having, wherein we discovered Kozelek was a little jealous about the Postal Service.)

Gibbard was in need of a little friendly assistance at the concert because he recently broke his wrist running in the Orcas Island 50K. According to a post on Instagram, he "banana peeled on a super-slick bridge."

Fans of Kozelek will soon have more cause for happiness, as Sun Kil Moon just announced the impending release of a new album, Universal Themes, set to come out June 2.

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