Just a couple of days after Axl Rose's habitual tardiness sparked an apparent mass exodus at a London Guns N' Roses show, the band made up for it by giving fans at their Thursday (May 31) concert a little something extra: A surprise appearance from former GNR guitarist Izzy Stradlin.

Stradlin, who's rejoined the band on tour periodically since quitting in 1991, stepped out on stage for six songs: 'You Could Be Mine,' Dead Flowers,' 'Knockin' On Heaven's Door,' 'Nightrain,' 'Paradise City,' and '14 Days.' As Blabbermouth notes, GNR haven't performed '14 Days' live since 1991 -- coincidentally, also at a London show.

Rose has generally seemed to have an open-door policy with Stradlin since he left the group; when Izzy's replacement, Gilby Clarke, was unavailable for a string of shows in 1993, he temporarily rejoined the fold to fill in. Stradlin returned to the lineup in 2006, serving as a surprise special guest at a New York show before hitting the road with the group for 13 European concerts.

In recent years, it might be understating things somewhat to say that Stradlin has focused on his solo career; between 2007 and 2010, he treated fans to a torrid burst of creativity, releasing five albums of new material. He hasn't released anything since 2010's 'Wave of Heat,' which featured his former Guns bandmate Duff McKagan on bass, but he's clearly still playing -- and if this GNR reunion is anything like the last one, it could signal plenty of new music from Stradlin.

Watch Izzy Stradlin Perform with Guns N' Roses, May 31, 2012

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