Reflecting on a riotous two-hour fug of near-uninterrupted hits played with demented brio by four old friends with unfinished business to address, one or two nagging questions followed us into the dying midsummer light. How could we have forgotten that they were quite this good? And while we were at it, how did we think that, between Oasis’s one-trick mule and Blur’s three-ring Britpop circus, it was a close-run thing?

In fairness, it might not just have been us. In the six years since he last sang with Blur, Damon Albarn seems to have lived in denial of his talents as a proper old-fashioned, look-at-me frontman. Yes, in a low-key sort of way, interim projects Gorillaz and The Good, The Bad & The Queen had seen him singing. But, returning to Goldsmiths — the art college where Blur formed 20 years ago — he donned his de facto Britpop work clothes (Fred Perry and blue jeans of course) and reminded us what a superb pop star he is.

Most groups would save songs with the pedigree of Girls And Boys and There’s No Other Way for the final stretch. Looking exceptionally well-preserved, Blur spat them out within the first 15 minutes.

On Tracy Jacks an audience whose perfect recall of the words hadn’t diminished with the years helped out with the words. A visibly delighted Albarn urged caution: “You should probably pace yourselves ’cos there’s a long way to go.” Sound advice perhaps, although he didn’t follow it and neither did anyone else. There were impromptu stage dives from the 41-year-old singer, scissor kicks from a bespectacled Graham Coxon, and touchingly — considering the brief estrangement that saw Blur’s 2002 album Think Tank recorded without Coxon — several fond exchanges between the two. It was enough to make your eyes mist, were it not for the fact that several songs were doing a perfectly good job of that on their own.

Really, it was outrageous how ceaselessly they would pull out another song whose imperishable magnificence somehow caught you unaware. Beetlebum — the 1997 hit that saw Blur redefine their sound and put some serious distance between themselves and Britpop — drew from a deep emotional well. Perched on the monitor like a rakish meerkat, Alex James seemed close to tears as the rest of the band navigated the song’s aching melody into something more visceral — Albarn attacking his acoustic guitar with finger-grating intensity.

Audience participation wasn’t so much a choice as one long, lovely reflex action. Tender — Albarn’s 1999 lullaby-cum-requiem to his relationship with Elastica’s Justine Frischmann — was a full-throated singalong that seemed fleeting at seven minutes. On This is a Low, Dave Rowntree’s cymbals caught the light as they crashed like an electrical storm.

When they finally got around to them, it took the opening chords of Parklife to set off a Proustian avalanche measured out in the finger-jabbing zeal with which everyone bellowed out the chorus. On Song 2, the wooh-hoos started before the tune even got going — fans goaded into action by Dave Rowntree’s slowly accelerating drum intro. Respite eventually came in the encore when Blur lowered the tempo with For Tomorrow. Back in 1992, this was a sad, sweet love song Albarn penned for the city on which he had yet to truly make his mark.

Seventeen years later, you’d think his hunger to prove a point must have diminished in some way. And yet, having seen him spend the best part of two hours tearing into his band’s stockpile of hits like a dervish with a grudge, we knew that was anything but the case. If this was, as billed, a warm-up show for the real business of the summer — a pair of festival dates and two Hyde Park headlining shows — then one shudders to think what they still have in reserve.

Blur play Glastonbury this weekend; Hyde Park July 2-3 (Sold Out)

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