After some early spells of possession for both teams, it was Arsenal that went ahead with the first meaningful chance of the game.
Mikel Merino’s through ball found Ethan Nwaneri, and the 17-year-old slotted coolly under Bart Verbruggen and into the bottom corner.
Simon Adingra squandered Brighton’s best chance to equalise before half-time, scuffing Matt O’Riley’s pass wide from a promising position.
Arsenal came back again, and Nwaneri almost scored a brace when his corner flicked off the outside of the post, before Gabriel Jesus headed another corner over with Declan Rice the deliverer this time.
Another Arsenal set-piece early in the second half saw Merino skew wide when he should have done better after connecting with Rice’s delivery.
Just a couple of minutes later, the missed opportunity would be punished, as Brighton were handed a penalty when Joao Pedro was accidentally headbutted by William Saliba, who had tried to head the ball away.
Pedro stepped up himself and wrong-footed David Raya, placing the ball neatly into the top corner.
The hosts had their tails up now, and substitutes Yankuba Minteh and Kaoru Mitoma almost combined to turn the match around, as the former fizzed a dangerous ball across goal.
Both sides held on for a point in a nervy last few minutes, with Brighton now winless in eight league games, and Arsenal having to settle for another disappointing draw against the Seagulls, after the same scoreline occurred in the reverse fixture.