Sex Pistols drummer Paul Cook has looked back on the band’s firing of bassist Glen Matlock in 1977, admitting the decision was a mistake.

“The story around Glen leaving or departing or being sacked, whatever, is pretty messy,” Cook explained during a recent appearance on The Rockonteurs podcast. “John [Lydon] and Glen had fallen out over some reason. I don’t know why. They weren’t getting on. And John felt that it was me and Steve [Jones] now against [him]. We were a tight-knit couple, if you like. And John felt like he needed a bit of someone in the band who was on his side.”

Malcolm McLaren, the band’s manager, sided with Lydon and suggested Sid Vicious should be the group’s new bassist.

“It was the only time Malcolm and John were in alignment with anything, really,” Cook recalled. “They were manipulating the situation to get rid of Glen and get Sid in the band.”

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Vicious – real name Simon Ritchie – had been an avid fan of the Sex Pistols. He was a constant presence at the band’s shows and was well known by the musicians.

“He was at all our gigs early on, causing trouble, inventing the pogo, jumping up and down, smashing into people,” Cook remembered. “And he desperately wanted to be part of it.”

The drummer noted that McLaren saw Vicious as a valuable addition to the band’s image, and didn’t care that he’d never played bass before. Matlock, on the other hand, had been a valuable contributor to Sex Pistols’ music.

“It was a stupid thing we could have done, getting rid of Glen,” Cook admitted. “We was all writing great songs together.”

Paul Cook Says He ‘Should Have Stuck Up’ for Glen Matlock

In hindsight, the drummer conceded that he should have fought to keep Matlock in the group.

“Me and Steve, we just went with the flow. We didn’t want to upset the apple cart. They made it seem like, ‘If Glen don’t go,’ this is Malcolm and John, ‘no, that’s the end of the band.’

“So we took the easy route. We didn’t stick up for him, much to my regret, really,” Cook continued. “We should have stuck up for him. But things was going so crazy at the time. We just thought, oh, it’ll be alright. We’ll work it out. And we didn’t realize what we were taking on with the Sid.”

Sex Pistols ‘Soon Deteriorated’ After Sid Vicious Joined

While Cook admitted Vicious was great “image-wise,” he noted that the new bassist had a toxic effect on the Sex Pistols.

“It totally changed once he joined the band. Totally. The dynamic changed. Totally changed. Got crazier, for the worse,” the drummer explained, adding that things “soon deteriorated” after Vicious joined.

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Sex Pistols broke up in January of 1978 following a disastrous U.S. tour. That October, Vicious was arrested and charged with the murder of his girlfriend, Nancy Spurgen. He died of a drug overdose four months later.

Matlock eventually rejoined the Sex Pistols for their unexpected 1996 reunion. More recently, he joined Cook and Jones for a pair of shows to raise money for London music venue Bush Hall. Lydon, who has had his own long-running disputes with his former bandmates, didn’t not take part. Instead, singer Frank Carter filled in on vocals.