Bono had a nerve. Specifically, he had one in his back. The Irish singer had crushed it while rehearsing for one of the biggest shows of his life. And it caused havoc down on Worthy Farm.

It was May 2010 and U2 were a month away from headlining that year’s Glastonbury Festival, where 175,000 revellers would gather to celebrate the Somerset shindig’s 40^th anniversary. Organiser Michael Eavis had spent years trying to convince the band to play. They’d finally agreed to top the bill on the Pyramid Stage on the opening night. Then Eavis received the call. Bono needed emergency surgery for severe compression of his sciatic nerve. The show was off (as were a string of other planned U2 dates). In a statement on May 25, Bono said he was “heartbroken” – the band had even written a song especially for the festival. Eavis was “gutted.”

Bono’s crocked back gave the Glastonbury organiser a monumental headache. With just weeks to go, he needed to find a replacement headliner for the Friday night of the most famous music festival in the world. It was a daunting prospect. Luckily he didn’t have to wait long. Within 24 hours of U2’s withdrawal, Damon Albarn and Jamie Hewlett’s cartoon band Gorillaz had offered to headline.

It was the perfect solution. Gorillaz’ 2005 album Demon Days had sold five million copies and its follow-up, Plastic Beach, had been released that March. The band had hits, commercial clout, and always used well-known guests in their live shows – ideal for a headlining slot. A clearly-relieved Eavis promised that Gorillaz’ set would be a “massive audio-visual spectacle” with “astonishing alchemy”. Aware that he’d been thrown a lifeline, he added that he was “so grateful for the enthusiasm of the media and the whole of the music industry for their willingness and eagerness to support us in what could have been a crisis”.

Gorillaz themselves trumpeted their involvement. Via a band statement, their fictional bassist Murdoc Niccals likened their actions to “some great big horrible warship pulling in to the Bay of Glastonbury to save the day”. He said: “It was us or the Beatles and they split up years ago.” (Ironically, a dozen years on, Paul McCartney will headline this year’s 50th anniversary festival with a set packed with Beatles hits). 

Referencing U2 and hinting at numerous on-stage collaborators, Niccals went on: “The previous soldiers got pulled from duty last minute so it’s up to my Plastic Beach naval cavalry to sail in and sort the battlefield out. I can assure you though, I’m bringing extra troops. Loads of them. Glastonbury will be ours… cutlasses drawn, trumpets ready. We’re coming…”

But Gorillaz didn’t save the day. Glastonbury wasn’t theirs. At least, not at the time it wasn’t. Their hotly-anticipated show was met with poor reviews, Eavis’s promise of an audio-visual spectacle rang a little hollow, and the crowd noticeably thinned as the set progressed. This newspaper described the show as a “disappointment” and said that it was “starkly obvious” that Gorillaz were not a headline band. My former colleague Lucy Jones coined a neat pun to describe the show: Gorillaz snorefare. The Guardian was no more polite, saying that the set “failed to ignite” and even “ground to a halt” at one point. Eavis’s big gamble of booking the band “didn’t pay off”, the paper said. Gorillaz’ great big warship listed badly in the bay.

Fans were disappointed and bemused. One told Gigwise that Gorillaz had “bombed”. Another fan, Stevo, wrote on an online forum days after the event that he was “bored along with nearly everyone else… Whoever booked that pile of pretentious poo to headline needs their head examined.”

Now, retrospect is a fine thing. It’s always easy to look back on events through rose-tinted spectacles. But I was there that night. I believed it at the time and I still believe it now: Gorillaz’ headlining set of 2010 has been unfairly maligned. Far from being a disaster, it was raggedy, high-concept, eccentric triumph with moments of sheer brilliance. It was far from perfect. But over 18 visits to Glastonbury I’ve had the opportunity to see 54 Pyramid Stage headliners (I didn’t see them all) – and Gorillaz will forever be in my top handful. I’m prepared to defend them, cutlass drawn, trumpet ready. But first, here’s what went wrong.

Gorillaz were, at the time, a band in transition. Before Plastic Beach, they largely performed as their cartoon characters: animations of the “members” – Niccals, 2-D, Noodle and Russel Hobbs – were projected on screens at the front of the stage with the actual musicians either playing hidden behind those screens or subtly silhouetted in the background. The Demon Days Live tour of 2005 also featured lifesize puppets created by Jim Henson’s workshop. At the 2006 Grammy Awards, holograms of Niccals and his cartoon chums duetted with Madonna. But for Plastic Beach, everything was inverted.

For the first time, the real musicians played up front undisguised while videos of the virtual members were relegated to screens at the back and sides. It would have made for a more engaging live performance except for one thing: Albarn was still in “hidden” mode. He barely talked to the Glastonbury crowd. He failed to introduce the astonishing array of guests – Lou Reed, Bobby Womack, The Fall’s Mark E Smith, De La Soul, Kano, Bashy, Shaun Ryder, to name just some – meaning that the crucial element of interaction was missing. 

There was no connection and some confusion. To the younger members of the crowd, Velvet Underground legend Reed could have been a lookalike of England football manager Fabio Capello for all they knew (2010 was a World Cup year and England would be knocked out by Germany two days later). When Mark E Smith read his lyrics off a piece of paper, he might have got away with it had he been introduced as the post-punk legend that he was. With no introduction, though, he looked like a taxi driver who’d wandered onto the Pyramid by mistake. For a headline act, this was misguided.

Then there was the setlist. Gorillaz played all but two tracks from the new Plastic Beach album, shunning five early singles. A Syrian orchestra played an interesting but hardly attention-grabbing (and very quiet) introduction to the track White Flag. The audience drifted. There was an excruciating moment towards the end when Albarn tried to get the crowd to sing along to a refrain in the environmentally-themed album track Pirate Jet. It was a tuneless line about leaving the taps dripping for a hundred years, repeated many times. Barely anyone joined in, leading an increasingly desperate-looking Albarn to mouth “please” to the audience.

But the biggest problem was nothing to do with the show itself: it was what had happened the year before. In 2009, Albarn’s reformed band Blur had headlined the Pyramid Stage and nailed it. The kings of Britpop played a set full of bangers, interaction, singalongs and joy. It ended with Albarn breaking down in tears at the emotion of it all. He’d set his own bar pretty high, and Gorillaz suffered by comparison.

But here’s what went right. Gorillaz played and looked like a gang that night. Dressed in what I’d describe as “dystopian nautical punk” attire – wonky captains hats, Breton tops, Navy pea coats – they flooded the stage with attitude. Bass duties were performed by The Clash’s Paul Simonon, who was clearly one of the real-life influences for the cartoon Niccals in the first place. His former bandmate Mick Jones played rhythm guitar. That’s right: half of The Clash were headlining Glastonbury. A seven-strong string section sat in the middle adding depth and colour to the music of a core band of nine. There were two drummers, which is always a thrill. The poster that would publicise Gorillaz’ subsequent tour lined up the musicians in a motley row and was based on the poster for Sam Peckinpah’s 1969 western The Wild Bunch. It was apt. There was a crackling outsider energy there.

Then there were the guests. Despite the lack of introductions, the collaborators were like a Who’s Who of pop history. Almost every genre from the music spectrum was represented: R&B and soul with Womack, alternative rock with Reed, post-punk with Smith, baggy indie with Ryder, daisy age US hip hop with De La Soul, British rap and grime with Kano and Bashy, world music with the Syrian orchestra, and electronic music with Little Dragon. A little over a decade on, it almost feels like a different era. Many of the guests are no longer with us. Reed died in 2013, Womack in 2014 and Smith in 2018. It’s unlikely that music’s great kaleidoscope will ever be represented in such a way in a single set again.

Yes, the setlist could have been tweaked to include a few more early hits or – missed opportunity here – some Clash tracks with a Gorillaz twist. Guns of Brixton, Rock the Casbah, Straight to Hell or Bankrobber could have been incredible Gorilla-fied. But we got Dirty Harry, Dare, Stylo and Feel Good Inc. There was also a goosebump-inducing performance of On Melancholy Hill, now seen as an Albarn classic but then a new and relatively unfamiliar single. But watching the band perform it under clear but darkening skies, with Glastonbury Tor visible in the distance and campfires flickering all around, was both magical and unforgettable. “Cause you are my medicine / When you’re close to me,” Albarn sang before that earworm synth hook. That was the Glastonbury spirit right there. That was togetherness.

And this is the thing about Glastonbury 2010. It was deliciously hot. It was one of those rare years when you weren’t cold, there was no mud so you don’t have welly blisters, it was not a squelchy mission to walk anywhere, and you were not wishing you were tucked up in your sleeping bag. It was about the moment. Add to that the fact that, as mentioned, it was a World Cup year (albeit short-lived) and there was a sort of heightened bonhomie in the air.

The highlight of Gorillaz’ set, however, came at the end. The familiar melodica refrain and languorous bass of the song Clint Eastwood was followed by the appearance of Snoop Dogg. It was known that the rapper was on site as he’d played on the Pyramid earlier in the day, but many assumed he’d join Gorillaz ­– if at all – for an earlier song on which he’d appeared on the recorded version. He hadn’t, so people thought that was that. Yet here he was, rapping the lyrics of his own hit Drop It Like It’s Hot over Clint Eastwood and having a ball in the process. There was a lovely moment when Snoop’s dance move (a sort of knees-bent-bum-wiggle-spinning-around combo) almost put the string section off the glorious Middle Eastern-style swoops they were adding to the song’s coda. The crowd went suitably bonkers.

This didn’t stop the bad reviews. And a month later, Albarn himself admitted he’d messed up by not talking between songs. “We were yet to change the dynamic entirely from the cartoon band acting purely as a film orchestra into something that had more of a human element to it,” he told the BBC. He’d immediately changed tack after Glastonbury. “Basically, the difference between that and the next gig we did at Roskilde [Denmark] – which was the same sized audience, same age demographic – was I just communicated with the audience more. I introduced Bobby Womack, introduced Lou Reed, introduced anyone. I didn't take for granted that if these people were going to be at the front then there had to be some kind of human interaction.”

As recently as 2017, reviews of Gorillaz shows still mentioned their lacklustre Glastonbury. But for me – and I imagine countless others – the memories are different. Sunshine in a bag? It certainly was.