U2’s current residency at the Las Vegas Sphere is going ahead without the involvement of drummer Larry Mullen, who is sitting out for health reasons.

The band had plenty of notice to bring in replacement Bram van den Berg – but that wasn’t the case the first time they performed without a co-founding member.

During their colossal two-year Zoo TV world tour, bassist Adam Clayton drank himself into such a state that it was impossible for him to take the stage. Yet the first of two appearances at the Sydney Football Stadium on Nov. 26, 1993, was simply too important to postpone.

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This was the de facto technical rehearsal for the following night’s concert, which would be broadcast around the world and later released on home video. With so much at risk, U2 had no choice but to soldier on. They performed the show with Clayton’s bass tech, Stuart Morgan. Before Mullen’s absence this year, it was the only time one of the four schoolboy friends had been missing since they took on the U2 name.

Being absent proved to be a life-changing experience for Clayton, who later admitted that his drinking had spiraled out of control. It started in Sydney with two glasses of wine, he said, and he couldn’t remember what happened next.

“I know about three days later I woke up and I hadn’t turned up for a gig, in a stadium, that was being filmed – a lot of money resting on it, a lot of jeopardy,” Clayton said. “I had let the guys down – the three guys who had stood by me since the age of 16 or 17. I mean, I’m sure it was unimaginable to them that could have happened. I let down the audience; I let down the road crew.”

Bono Joked About Adam Clayton’s Meltdown

Clayton admitted that “success very much went to my head. You lose your sense of yourself; you lose a sense of reality. I was kind of very unhappy so I drank and I drugged and got myself in tabloid newspapers, and embarrassed kind of everyone I knew – and myself.”

Clayton stopped drinking soon afterward. “You come through it, and you learn from it, and maybe that’s what young men do anyway,” he reflected, while noting he still had to “work really quite hard at keeping my sanity on and off the road.”

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Fortunately, he recovered in time to perform the filmed show the following night. If any evidence were needed that his determination resolved any issues with his lifelong colleagues, frontman Bono made gentle fun of Clayton when U2 performed in the same city in December 2010. “Zoo TV was broadcast to the world from Sydney. … Adam, you probably don’t remember that,” he said.

Speaking to Clayton, Bono admitted that “it was quite a weekend, but I think you do remember it as a turning point. And I would like to say, on behalf of your bandmates and your comrades, how in awe we are of the human being you’ve turned into.” He then told the audience: “Adam Clayton 2.0 started here in Sydney.”

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Gallery Credit: UCR Staff