Melvins drummer Dale Crover will sit out the band's imminent co-headlining tour with Boris to receive emergency spinal surgery.

"We are sad to announce that literally days before leaving on tour, our drummer Dale Crover learned he needed immediate emergency spinal surgery which will take him out of commission for months," the band wrote in a statement, which you can see below. "He's doing as well as can be expected considering the severity of the situation."

Crover joined Melvins in 1984 and has performed on all of the band's albums. He's been a constant member for nearly 40 years alongside singer and guitarist Buzz Osborne. His drum throne will be filled on the upcoming tour by Coady Willis, who served as their second drummer from 2006 to 2015 and also plays in the metal bands High on Fire and Big Business. Melvins noted in their statement that Willis "literally trained in sitting by Dale's side on too many tours to count."

The Twins of Evil Tour, which includes support from the aggressive Chicago two-piece Mr. Phylzzz, begins on Thursday in Los Angeles and continues through Oct. 14 in San Diego. Melvins will play their 1991 album Bullhead in its entirety, and Boris will play their 2002 album Heavy Rocks in full.

"With Mr. Phylzzz already on the road heading to L.A. from Chicago and Boris flying in from Japan, we all felt we needed to support Dale and the other bands on the bill, as well as the ticket holders, by continuing with the tour as scheduled," Melvins wrote. "We ask everyone's solidarity during this dark time. Obviously, our primary concern right now is Dale's health, and we're doing everything possible on our end to make sure he gets what he needs to make a full recovery."

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