The Foo Fighters have invited everyone from Stevie Nicks to Dave Grohl's surgeon onstage with them during their latest tour, and the tradition continued on Oct. 18, when the band's Castaic Lake, Calif., show included a guest appearance from Ratt drummer Bobby Blotzer.

As you can see in the fan-shot footage above, Blotzer joined the Foos for a cover of "Tie Your Mother Down," a single from Queen's 1976 album A Day at the Races. Calling the members of the band his "longtime friends," Blotzer basked in the afterglow with a Facebook post explaining, "They are truly one of the five-star bands around, and it was especially cool to be invited up to jam with them. They told me they had seen the new YouTube videos of Ratt and that they thought it sounded great. I told Dave and Taylor that we would love to do some dates with them."

As previously reported, Blotzer recently announced his intention to tour with a new lineup of Ratt, though those plans have been contested by guitarist Warren DeMartini, who has threatened to do what he can to put a stop to the tour — prompting Blotzer to fire back by accusing DeMartini of breaching his "fiduciary duty" to the band's corporation, which they jointly own.

Former Ratt bassist Juan Croucier, meanwhile, has started his own spinoff project devoted to delving into the band's catalog, and is already on the road.

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This Day in Rock History: October 20