One good turn deserves another. We recently reported that Sixx: A.M.'s James Michael and Nikki Sixx took turns onstage joining Disturbed for their rock cover song medley. Now a member of Disturbed has hopped onstage with Sixx: A.M. for a performance as well.

Drummer Mike Wengren was invited to the stage at San Antonio's River City Rockfest on May 29, manning the kit as Dustin Steinke stepped aside during a performance of "Life Is Beautiful." Fan shot footage of the performance can be seen above.

This follows the recent guest turns of James Michael on a cover of U2's "I Still Haven't Found What I'm Looking For" and Nikki Sixx during a cover of The Who's "Baba O'Riley" during Disturbed's Rocklahoma performance.

The openness to collaboration should not be a surprise, as Disturbed's David Draiman called for unity in the rock and metal worlds a few years back, shortly after the passing of Slayer's Jeff Hanneman. Draiman stated, "There is no room for / excuse for jealousy / contempt / hatred between those who should be supportive / caring brothers and sisters in the world of hard rock and heavy metal," later adding, "I have been, and forever shall be, a fan of, an addict of, and a champion of, all things rock and heavy metal."

Disturbed have also opened their stage up for guest turns from Papa Roach's Jacoby Shaddix and Halestorm's Lzzy Hale on their current tour. Meanwhile, Sixx: A.M.'s founder, Nikki Sixx, has regularly championed hard rock and metal acts on his Sixx Sense radio show.

Sixx: A.M. are currently touring in support of the first volume of their Prayers for the Damned album, while Disturbed are continuing promotion of Immortalized. See Sixx: A.M.'s tour dates here and Disturbed's dates here.

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