If Michael Oliver isn’t on Oliver Glasner’s Christmas card list then the Crystal Palace manager may want to get one in the post before it’s too late. With the visitors struggling to get out of their half against Brighton’s onslaught, the referee was responsible for the game’s pivotal moment midway through the first half.

Fabian Hürzeler was left incensed by Oliver’s decision to allow play to continue after Carlos Baleba had been impeded by the official during a Palace break, with Trevoh Chalobah compounding his misery by slamming home from the corner that eventually resulted. Yet the Brighton manager was rightly disappointed by the way his side allowed their emotions to get the better of them as Ismaïla Sarr scored twice to seal a memorable victory for Palace over their arch-enemies that ended their unbeaten record at home this season.

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The only blemish for Glasner was Marc Guéhi’s late own goal that denied the otherwise outstanding Dean Henderson a deserved clean sheet and a booking for Daniel Muñoz that rules him out of Wednesday’s EFL Cup quarter-final against ­Arsenal, not that the jubilant away fans will particularly care after suffering the ignominy of a 4-1 defeat here in February under Roy Hodgson.

“It’s a big win because we know how important this game is for our fans,” said Glasner, whose side have moved up to 15th and have lost only once in their past nine matches in all competitions.

Having started so positively, this was the latest setback for Brighton against another team from the lower half of the table that have proved to be their weakness so far this season. Hürzeler’s side have also conceded 18 times in their past nine matches but he criticised Oliver’s decision not to stop play even though regulations state officials only have to do so if the ball hits them.

“When the referee says after the game that it’s his mistake then I don’t understand why he doesn’t stop the game,” he said. “So that’s an unbelievable decision that something like that can happen here.”

These occasions are never for the faint-hearted and – spurred on by their home crowd – it was Brighton who seemed most fired up at the start when Kaoru Mitoma shot straight at Henderson after a lovely flick over the shoulder from João Pedro. The Palace goalkeeper was then perhaps fortunate not to be punished when he raced out of goal to clear a through ball and clattered into Yankuba Minteh. It was not the only time that Oliver would be under the spotlight on a busy afternoon.

Glasner looked increasingly frustrated as his side found themselves penned back inside their own half by failing to beat Brighton’s aggressive press led by the colossal Baleba. It needed the assistance of Oliver to finally get past the Cameroon midfielder when the referee unintentionally blocked his challenge on Eberechi Eze. Palace took full advantage from the resulting corner at the second attempt when Chalobah scored from close range after confusion in Brighton’s penalty box, with Hürzeler letting his feelings known to the fourth official on the touchline.

Things could have got even worse for Brighton had Bart Verbruggen not saved well with his legs from Muñoz. But Palace clearly smelled blood and when a marauding Tyrick Mitchell picked out Sarr at the back post to head home, the visiting supporters could not contain their glee. Hürzeler, meanwhile, looked stunned.

His response was to withdraw Tariq Lamptey for the second half and switch to a back three, introducing Julio Enciso off the bench. It needed a block from Max Lacroix to deny Mitoma after he found space inside the penalty area. A sharp save from Henderson kept out Lewis Dunk’s header from a free-kick when it seemed easier to score before the England goalkeeper was at full stretch to tip Enciso’s curler around the post.

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A careless backpass from Pervis Estupiñán that almost embarrassed Verbruggen would have proved terminal for Brighton’s hopes of a comeback. The Ecuador defender was again at fault when he was uncertain over a bouncing ball and Muñoz slammed home Sarr’s pass, only for Oliver to rule it out for a foul by the Senegal forward.

Hürzeler threw on the cavalry with 20 minutes to play and the substitute Brajan Gruda was a whisker away from halving the deficit with a dipping free-kick. But when Dunk dallied at the back it allowed the outstanding Sarr to score his second and ensure the bragging rights belonged to those of a red-and-blue persuasion for the first time since a 2-1 win here in February 2021.