update: Metallica [ tickets ] frontman James Hetfield on Wednesday night (7/12) returned to the stage to perform with his band during the group�s concert in Denver, according to Metallica�s official tour website. Hetfield was unable to perform at the band�s previous three appearances due to a back injury, although the rest of the group still performed without the singer.

Hetfield had been sidelined with two herniated disks, according to a statement from Elektra, and underwent numerous rehabilitative treatments before rejoining the group in Denver. His physical therapist was standing just off stage during the band�s Wednesday night (7/12) performance in case Hetfield ran into trouble, according to the band�s official tour website. No problems were reported.

Drummer Lars Ulrich, bassist Jason Newsted and guitarist Kirk Hammett played without Hetfield at the band�s Summer Sanitarium Tour stops in Atlanta on July 7, Sparta, Ky., on July 8 and Irving, Tx., on July 9. Members of other bands on the tour�s bill--which also features Korn, Kid Rock, Powerman 5000 and System of a Down--stepped in for the injured singer.

Despite the fact that Metallica, with the help of their tourmates, turned in a full set on all three nights, the band has scheduled makeup dates that will be free for holders of ticket-stubs from the shows the singer missed.

The Summer Sanitarium Tour continues Friday night (7/14) in San Francisco.

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