This was an object lesson in how to kill a game. Brighton had struggled to make much headway against Ipswich for almost an hour when Kaoru Mitoma’s shot squeezed in and, from there, they simply did not let go. Rather than sit back they pressed forward relentlessly; the consequence was a first league victory in nine and perhaps a platform to transform the picture of an often frustrating campaign.

When Georginio Rutter cleverly turned in their second goal eight minutes from time, Brighton could enjoy winning a top-flight match by two or more for the first time since the opening day. Rutter was one of three substitutes introduced by Fabian Hürzeler almost as soon as they went ahead; their power and energy from the bench meant Ipswich simply could not get out after that, a hitherto respectable performance dissolving into the night and the buoyancy of a promising Christmas period turning to lead.

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Having spent a blissful 24 hours outside the relegation zone, Ipswich return to the bottom three with harsh realities ringing in their ears. Perhaps they could point to a gamechanging moment in the 54th minute when João Pedro charged into Christian Walton after he had cleared a back pass. João Pedro was booked but the incident looked worse with each replay: the video assistant referee declined any opportunity to recommend a red card but he had made no effort to withdraw from the challenge and seemed lucky.

“He’s left a little bit on the goalkeeper, it is what it is, it’s not something we’re going to cry about too much,” said Kieran McKenna, who is never one for excuses and was keener to focus on how proceedings ran away from Ipswich. “I haven’t watched it back, I wasn’t screaming for [a red card].” He might not be so generous after a second viewing; meanwhile Hürzeler had no intention to offer a different interpretation. “I don’t see a red card for this, never,” he said.

Soon after that flashpoint a pass down the line from Joël Veltman caught out Jacob Greaves, who could only help the ball into Yasin Ayari’s path. Ayari passed left to Matt O’Riley, who quickly found Mitoma for a low finish that seemed to go through Walton. The keeper may have been unsighted by his defender Leif Davis; either way it was a costly and, at that point, rare sequence of loose defending from an Ipswich team that had been broadly on top.

“We didn’t defend the situation as well as we’d have liked and that changed the game,” McKenna said. “We were the better team up to the point of their goal.” It was a fair argument, although in the first 20 minutes Ipswich barely touched the ball. They did, though, keep their discipline and packed a punch once emboldened to spring forward. Nathan Broadhead’s low curler forced Bart Verbruggen to save with a strong hand; a similar strike from Liam Delap demanded action and, before half-time, Omari Hutchinson drew another smart stop from range.

If Wes Burns, a threat on the right without quite finding the right final pass, had not snatched a presentable opening wide before Mitoma’s blow then Ipswich may have been able to build on their recent momentum. In truth they barely left their own half once behind, Walton saving superbly to deny João Pedro a fresh twist in his pantomime villain’s turn and Rutter coming close before smartly punishing sloppy defending from a left-sided free-kick.

Rutter and his fellow replacement Yankuba Minteh ran riot in that final quarter; an Ipswich squad light on fit attacking options and unable to register new signing Jaden Philogene in time had no answers. They will not find life much easier when Manchester City, with two days’ extra rest, visit Suffolk on Sunday although last month’s win over Chelsea suggests an aptitude for the bigger occasion.

There was less to worry Hürzeler. He is seeing his own injury list shorten and felt that, helped too by a resounding FA Cup win up the road at Norwich five days previously, a corner may have been turned. “It wasn’t the best performance from us but this win should give us the self-confidence and belief back,” he said. “We try to regenerate now.” For Brighton, possibilities are opening up again.