With regular bassist Jason Newsted sidelined for up to nine months with arm and shoulder injuries, Rock Star Supernova [ tickets ] has tabbed former Black Crowes bassist Johnny Colt as a temporary replacement.

Colt will assume his new duties when the fledgling supergroup--which also features Motley Crue's Tommy Lee and former Guns N' Roses guitarist Gilby Clarke, in addition to frontman Lukas Rossi--kicks off its first tour with a two-night stand in Las Vegas beginning on New Year's Eve.

"Johnny's the guy," Lee said in a press release. "Gilby and I have known him for a long time. He's the kind of player that can plug in and immediately make his presence felt. You'll know what I mean when you see us live. We're ready to roll, folks."

Newsted, formerly of Metallica, recently suffered his injuries while trying to catch a 90-pound bass head that fell from atop his amplifier. The accident resulted in a torn anterior labrum in his left shoulder and a rotator cuff and bicep tear in the right. The combination of surgery and subsequent rehab could keep him out of the band's lineup for up to nine months.

"I'm freaking out, my heart was set on finally getting on the road with these guys but my main focus now is to build myself back to 100 percent," Newsted said in a press statement after the injury. "The stage is set for the band, I wish them the best of luck."

The group's self-titled debut album, which was recorded with producer Butch Walker (Avril Lavigne, Bowling For Soup), is due in stores Nov. 21.