“It could have been the voice, but it wasn’t.”

Although it’s mighty hard to picture any other voice except for James Hetfield’s singing such early Metallica classics as “Jump in the Fire”, “Whiplash,” and “Phantom Lord” early in their career, Hetfield was not entirely sure if he wanted to be the group’s lead vocalist.Supposedly, Armored Saint singer John Bush was considered a potential addition to Metallica, but obviously, this never materialized, with Hetfield continuing on as the group’s singer and rhythm guitarist.

But during Metallica’s series of 30th-anniversary concerts at the Fillmore in San Francisco during December 2011, one evening featured Bush joining the band on stage for a kick-ass rendition of “The Four Horsemen”.

During an interview with That Metal Interview Podcast, Bush looked back on the night of December 7, 2011, which, in addition to guesting on the aforementioned tune, saw Armored Saint open the show (transcribed by Ultimate Guitar).

“It was at the Fillmore, a small venue in San Francisco… For them, that is. And it was great. I think every night they played different songs, so it was crazy. Even Kirk [Hammett] had a music stand. It was pretty funny. They really did something different and really unique for the fanbase. And we were honored to play with them as a support act that particular night.”

“And then we had the plan of me coming out and doing ‘The Four Horsemen’, and telling the story and that it could have been the voice, but it wasn’t. But it was awesome, it was a great memory, and it was just a blast of a night.”

Bush, who also served as the singer of Anthrax from 1992 to 2005, still remained impressed with all the other special guests Metallica enlisted for these shows.

“A lot of really amazing musicians that were there: Lou Reed who’s passed on, and Kid Rock and King Diamond. And then throughout the weekend, it was amazing: people like Ozzy and Halford, you name it. So many different musicians there. It was cool, it was great.”