The legendary heavy metal band revealed their lead singer is seeking help for his sobriety and they will have to pull out on the rest of their tour.
Hetfield has longtime struggled with addiction.
"A Note from Lars, Kirk, and Rob ・・・ We are truly sorry to inform our fans and friends that we must postpone our upcoming tour of Australia and New Zealand," Lars Ulrich, Kirk Hammett and Robert Trujillo posted to the band's social media on Friday.
Revealing the news about Hetfield, they continued, "As most of you probably know, our brother James has been struggling with addiction on and off for many years. He has now, unfortunately, had to re-enter a treatment program to work on his recovery again."
Metallic insisted they will head Down Under "as soon as health and schedule permit."
Apologizing to fans, they added, "Once again, we are devastated that we have inconvenienced so many of you, especially our most loyal fans who often travel great distances to experience our shows."
They also made sure to thank their loyal followers for their "understanding" and "support for James."
Metallica was set to begin touring in Australia and New Zealand next month, but tells fans that all tickets will be fully refunded.
Hetfield has talked about his addiction and alcoholism in the past, most recently in 2017, when he told the Joe Rogan Experience that he had remained sober for 15 years.