It was more than the changed kit and the changed lineup that brought this change of result for Ipswich: up against decent Championship opposition, even Kieran McKenna’s second string would be among the best teams outside the Premier League.

Jack Clarke, emblematic of that difference, again scored twice as Ipswich, after four straight top-flight defeats since their third-round three-goal victory over Bristol Rovers, reached the last 16 of the FA Cup for the first time since 2007.

Coventry, semi-finalists last season, also changed their kit for charity, to navy blue, but the Sky Blues can now refocus on the push for the playoffs, which have become a realistic target since Frank Lampard’s arrival 10 weeks ago.

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This was Ipswich’s biggest win since beating Sheffield Wednesday 6-0 last March, back when winning promotion to the Premier League was the only dream in town. Now it is about retaining that status, although McKenna can evidently trust his second string on this evidence, even in all pink, for Cup duties.

George Hirst opened the scoring, from a penalty earned after 20 seconds, and Jaden Philogene claimed his first goal for the club after his £20m transfer from Aston Villa. But it was Clarke, who signed from Sunderland for an initial £15m late in the summer transfer window, who took star billing with his second double in the competition and overall display.

“The goals will be a boost for him, but I’ve got no doubt about Jack’s qualities,” McKenna, the Ipswich manager, said. “He’s shown it in training and his understanding of … the position, how he can affect a game, the demands of our group … is really growing.

“You can’t underestimate the jump for someone like Jack – and we’ve got a few players in that category – arriving late in the transfer window into a new group, never played in the Premier League, joining a club that haven’t been in the Premier League for 22 years. Trying to settle into the toughest league in the world as an attacking player is not easy.

“We know how talented he is as a player who signed for now and for the future. I’m sure he’s going to keep improving and today was not a big surprise to me.”

While Ipswich were humiliated by Maidstone United last year but gained promotion, Coventry knocked the non-league side out in the next round and went all the way to an epic Wembley semi-final shootout defeat by Manchester United. But their league form dropped off so much that Mark Robins, a legendary figure in these parts for leading the club from League Two to the lip of the Premier League in 2023, left in November. What price cup glory?

Coventry had won four successive league games to move to within three points of the playoff zone, before the harsh reality check of defeats here this past week to Leeds, the Championship leaders, and now Ipswich. “I think there’s a lot of context at this game,” said Lampard. “Ipswich were absolutely fantastic last year and go and bring a lot of new players in to compete in the Premier League, which is a gap. So they’re going to have that squad [and] they can make changes. [Then] they played last weekend; we played on Wednesday night and we’ll play on Tuesday night.”

It did not help that Coventry conceded a penalty almost from kick-off. Sammie Szmodics, briefly back from an ankle injury that forced him off before half-time, was bundled over by Liam Kitching and Hirst converted from the spot.

Joel Latibeaudiere headed Coventry level from Jack Rudoni’s corner but Ipswich, notwithstanding the 11 changes to the side who lost at home to Southampton, always looked sharper.

Clarke took over the scoring duties. First the former Leeds winger cut back inside and swerved his shot low into the far bottom corner. Then he took a touch to control Nathan Broadhead’s pass, after a defensive mix-up, and score to make the game all but safe.

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Coventry came out for the second half with fire in their bellies, but after Philogene prodded home at the far post from Clarke’s low cross, the result was done. So Ipswich can claim the Cup glory, albeit with their first team rested up for next Saturday’s game with Aston Villa, while Coventry must pick themselves up for Tuesday’s visit from QPR. The promised land of a top-flight relegation battle this time next year is still within their sights.