Arsenal overcame the hurdle of a North London derby and an anxious finale to maintain momentum in the Premier League title pursuit with a vital victory at Tottenham.
Mikel Arteta's side moved four points clear at the top of the Premier League, with second-place Manchester City, who have two games in hand, playing in the later kick-off at Nottingham Forest (16:30 BST).
The Gunners' meeting with their bitter rivals was seen as arguably the most treacherous of their remaining fixtures, but they took ruthless advantage of Spurs' defensive flaws to establish a three-goal lead by half-time.
Arsenal were then thrown off course when a dreadful clearance by goalkeeper David Raya presented Cristian Romero with a goal after 64 minutes, the nerves jangling when Heung-min Son scored from the spot three minutes from the end of normal time after Declan Rice fouled Ben Davies.
It was all so different when Arsenal went ahead after 15 minutes as the recalled Pierre-Emile Hojbjerg glanced Bukayo Saka's corner into his net, the England forward crowning a sweeping counter-attack with a smooth finish for the second after 27 minutes.
Spurs, who saw Micky van de Ven's goal ruled out for a marginal offside with the score 1-0, were infuriated as they claimed Leandro Trossard had fouled Dejan Kulusevski before Saka scored and were even more frustrated when the unmarked Kai Havertz headed in Arsenal's third from another corner seven minutes before the break.
Arsenal were then content to see out the victory, only for Raya to give Spurs hope by sending a clearance straight to Romero.
An unlikely comeback seemed on when Son scored from the spot but Arteta's side were able to close out the game, denting their arch-rivals' hopes of a top-four finish.
Spurs remain in fifth place in the Premier League, seven points behind Aston Villa with two games in hand.
Arsenal went from cruising comfortably to hanging on in a thrilling north London derby, a stroll to victory made hazardous by their own mistakes.
The Gunners were never actually near their best but when the season reaches this point it is about winning and the job was eventually done, but not without a nail-biting finish.
