Ipswich’s wait is over. Portman Road would not be denied its first Premier League win since April 2002.

Liam Delap did the damage, winning a penalty he clattered home, then laying up Omari Hutchinson for the second, a barnstorming performance. If Ipswich won hope in their battle against relegation, then Enzo Maresca’s targets for Chelsea are being redrawn to remaining in the top four.

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Any mooted title challenge, such as it was, will not reach 2025. Two defeats and a draw over the festive period leave them 10 points behind Liverpool, not so much holding on to coattails as left for dust. At full-time, Ipswich began a lap of honour McKenna tried his best to dampen, mindful of huge challenges ahead, though that was delayed by a fracas where Chelsea tempers had clearly frayed.

“No one expected us to be where we are,” Maresca said. “We are in a good position but we can do many things better. We are not focused on the title race or those things.”

Had he taken Ipswich too lightly? Maresca’s reputation as a decisive manager was enhanced by dropping Robert Sánchez for Filip Jörgensen after a costly goalkeeping error against Fulham, but his other selections flopped. With a sizeable squad to hand, and clear signs of fatigue, the selection bore a resemblance to a Conference League team, particularly in the presence of the mysterious João Félix.

Was a factor Ipswich’s status as a bottom-three club without a home win all season? McKenna, a contender for the job that went to Maresca, ended up extending Chelsea’s blue Christmas. He, too, had shuffled out a keeper, Christian Walton replacing Arijanet Muric, and after a fine display it was the League One veteran who led the post-match chorus.

“One of the best nights,” McKenna said. “We’ve been privileged to have a lot of good nights.” Six of his starting lineup had played League One football under him.

Chelsea were caught cold. Delap crashed into Levi Colwill with unseasonal intent to begin his wrecking‑ball display. The early energy brought swift reward. Leif Davis’s ball sent Delap away and Jörgensen’s penalty-box challenge was hasty. Did Delap accentuate contact? It looked that way but the referee’s call was followed.

Delap drilled home and might have had another soon after, only for Jörgensen to partially redeem himself. Chelsea were sluggish, as lethargic in attack as defence, Félix incapable of staying upright. His re‑signing remains a riddle. Christopher Nkunku, equally, was slow to pounce when Cole Palmer’s free-kick hit the post, the Frenchman failing to beat Walton.

Ipswich’s soft underbelly, so often weighing down a team who win hearts through attacking play, was exposed when Palmer’s pass found Félix in position to score and then perform an elaborate celebration targeted at the haters. Problematically for the one-time €100m-plus playmaker, he had been half-a-yard offside. Disturbingly for Ipswich, Palmer was now strolling with intent, with far too much freedom.

As the half closed, bull-like on the counter, dragging Chelsea defenders off him like rag dolls, Delap forced a near-post save from Jörgensen, in turn matched by Walton acrobatically tipping over a Palmer rocket. The Wythenshawe wizard smiled ruefully, with the confidence of expecting more where that came from. And yet it never arrived. Palmer became lost in the fug of Chelsea’s inferior second half.

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They at least began the second half with heightened energy. Long moments of heavy pressure asked existential questions of Ipswich; surely life in the Premier League is about more than last-ditch defence only to lose?

The answer Ipswich have been looking for since August came with their second goal. Axel Disasi, close to a headline-writer’s dream, played a no-look pass into Delap’s path. The striker’s intelligent cutback gave Hutchinson room to score against a club that discarded him and celebrate with a backflip of vindication.

“Copy and paste, we conceded the goal because of a mistake,” Maresca said. His immediate response was to end Félix’s evening. On came Nicolas Jackson. Nkunku soon departed, not much less ineffective. Delap – the one‑man, 21-year-old attack – was meanwhile having the time of his life.

Teasing the ball past Moisés Caicedo and then holding off Marc Cucurella, he forced another save from Jörgensen, whose overall performance suggested the wisdom of Maresca’s selection in that department had been correct. Jackson missed a one‑on-one as Chelsea began to flail with the frustration that eventually boiled over. Ipswich could begin the celebrations with 2024, a landmark year in the club’s history, closed in style.