US heavy metal legends Metallica have been forced to postpone their September 3 concert in Phoenix after announcing that frontman James Hetfield has tested positive for Covid-19.

"We're very sorry to report that tomorrow's scheduled M72 date at State Farm Stadium has been postponed to Saturday, September 9, 2023, as, unfortunately, Covid has caught up with James," the band said in a statement shared on its official account on X, the site formerly known as Twitter.

"We're extremely disappointed and regret any inconvenience this has caused you. We look forward to returning to complete the M72 No Repeat Weekend in Glendale next Saturday," the band added.

The show, originally scheduled for Sunday, would have been the last of two in Glendale, Arizona. The band is currently on its M72 tour in the US and plays two concerts in every city.

Tickets for the September 3 show "would be honored on September 9," the band said.

Covid-19 cases have been on the rise in the US this summer.

Nationally, the new EG.5 variant, a spinoff of the XBB recombinant strain of the Omicron family, is driving most new infections, according to the latest estimates from the US Centers for Disease Control and Prevention.

Although rates of severity currently remain at relatively low levels as compared to the start of the pandemic, medical experts agree that there are probably more infections than current surveillance systems can capture and are warning about a resurgence of the virus.