Friday, Mustaine posted a message to Twitter asking his followers which song the two should play together.
Mustaine will perform with Megadeth, headlining BFD July 12 at Gexa Energy Pavilion. Newsted will also take the stage with his eponymously-named band.
Newsted was Metallica's bassist 1987-2001, and Mustaine was the band's original guitarist until being fired and replaced by Kirk Hammett in 1983. The latter is credited with co-writing several songs on Metallica's early albums.
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