Arsenal moved five points clear at the top of the Premier League after Declan Rice's last-gasp goal capped the leaders' thrilling fightback in their 4-3 win against Luton on Tuesday.
Rocked by a pair of costly blunders from keeper David Raya, Mikel Arteta's side trailed 3-2 in the second half of a pulsating clash at Kenilworth Road.
But Arsenal roared back to consolidate their lead at the top of the table thanks to Kai Havertz's equaliser and Rice's header deep into stoppage-time.
The wild celebrations from Arteta and his players underlined the significance of a gritty escape that will fuel the belief Arsenal can finally win their first title since 2004.
"I'm so happy. We knew it would be a big battle here, we made it hard for ourselves the way we conceded the goals," Arteta said.
"The spirit of the team, how we fought, showed our quality in the right moments and never gave up. We went for it and got our rewards today.
"Big compliments to Luton, it was a tough night. I've spoken with the team, and they are all jumping."
Gabriel Martinelli had opened the scoring for Arsenal, with Luton's Gabriel Osho equalising and Gabriel Jesus restoring the visitors' advantage just before half-time.
Elijah Adebayo scored Luton's second equaliser soon after half-time thanks to the first of Raya's mistakes and Ross Barkley benefitted from another error from the Spaniard.
But England midfielder Rice had the last word to give Arsenal six successive wins in all competitions since their controversial VAR-aided defeat at Newcastle.
Second-placed Liverpool can close back to within two points of Arsenal if they win at bottom-of-the-table Sheffield United on Wednesday.
Arteta's men have been road warriors since the start of last season - winning 17 away games in that period -- and the Gunners' first trip to Kenilworth Road for 32 years brought their first victory at the venue since 1984.
They struck first in the 20th minute when Bukayo Saka weaved his way down the right flank for a low cross that Martinelli met with a scuffed finish into the bottom corner from 12 yards.