Arsenal eventually saw off a stubborn Brighton to move back to the top of the Premier League – where they remained after Liverpool were held to a goalless draw by Manchester United.
The Gunners, now a point clear at the summit, claimed their success thanks to Gabriel Jesus’ header and Kai Havertz’s late strike.
Mikel Arteta’s side dominated the first half against Brighton without reward, but the tension eased when Jesus turned in after a corner.
The hosts were almost punished when Pascal Gross poked a golden chance wide before Havertz sealed victory to spark joyous celebrations among a relieved home contingent.
The Seagulls, who were looking for a third successive league victory at Emirates Stadium, managed just one shot on target and drop to ninth place.
After a conservative first-half performance, Brighton offered more attacking threat in the final half an hour but anything other than a home win would have been scarcely deserved.
Arsenal had 26 shots in the match and almost added a third in injury-time when substitute Emile Smith Rowe’s low drive was saved.
“It was an incredible performance. It was a joy to watch from the start to the end,” said Arsenal boss Arteta, whose jubilant celebrations indicated the magnitude of the win.
“The way we played against a phenomenal Brighton side was incredible. We were patient, kept going, kept believing and got what we deserved.”
With Liverpool frustrated at home by United, Arsenal now have 39 points from 17 games and next head to Anfield on Saturday for a crucial meeting with Jurgen Klopp’s side.
Arsenal continue to ask questions of Liverpool and Man City
With Liverpool playing later on Sunday, and defending champions Manchester City still behind them after dropping points against Crystal Palace, Arsenal had an opportunity to throw down the gauntlet to their rivals.
Losing a pulsating contest at Aston Villa last weekend had seen the Gunners’ relinquish their spot at the summit and a five-match winning streak in the top flight come to an end.
Nevertheless, the mood in the camp remained upbeat with Arteta and his players stressing the positives from a defeat where they had created enough decent chances to earn something.
Against Brighton, Arteta kept faith with the same starting XI and urged them to make amends in front of their home fans.
The Gunners were unbeaten in 12 home games – since losing 3-0 to Brighton in May – but the first half followed a familiar pattern.
Arsenal moved the ball with pace and purpose against a deep-lying Brighton side, creating several chances for Bukayo Saka, Martin Odegaard, Gabriel and Gabriel Martinelli in a one-sided first half.
However, they were unable to find the ruthless streak which Arteta had demanded.
