Declan Rice's last-gasp header snatched victory for Arsenal in a seven-goal thriller at Luton to move them five points clear at the top of the Premier League.
It was the conclusion to a compelling encounter in which the hosts twice fought back and threatened to win when Elijah Adebayo and Ross Barkley scored in an eight-minute period after the break, with Arsenal goalkeeper David Raya culpable for both goals.
However, the Hatters were denied a valuable point when Rice met Martin Odegaard's cross in the seventh minute of stoppage time, 23 seconds after the six official minutes added on had expired.
Arsenal had dominated a largely uneventful opening to a game which sparked into life when Gabriel Martinelli steered Bukayo Saka's pass into the bottom-left corner.
Gabriel Osho's header from Alfie Doughty's corner brought the hosts level shortly after, but when Gabriel Jesus nodded in Ben White's cross from close range the Gunners looked to have regained control.
But in a chaotic period after the interval, the league's best defence suddenly appeared flustered with Adebayo leaping above Raya to head in another Doughty delivery from a corner.
And with Luton in the ascendency, Barkley collected an Andros Townsend pass and beat White before driving a low left-foot shot under Raya.
The momentum swung back towards Mikel Arteta's side when Kai Havertz prodded in from the impressive Jesus' pass to equalise, but Luton looked to have held the visitors at bay until Rice's dramatic intervention.
The result leaves Luton 17th, two points above the relegation zone. Second-placed Liverpool, five points adrift of Arsenal, play their game in hand at Sheffield United on Wednesday (19:30 GMT), while Manchester City, a point further back, are at fourth-placed Aston Villa (20:15).