After Danny Welbeck's 95th-minute winner locked a 2-1 victory over 10-man Leicester, Arsenal breathed life back into their Premier League title charge.
Following Danny Simpson's dismissal for a second bookable offence, after the league leaders looked to have survived 40 minutes with a man down, Welbeck struck late on to break Leicester's resolve.
Until substitute Theo Walcott struck 10 minutes after coming off the bench to ignite a late Arsenal revival, Jamie Vardy's first-half penalty seemed to have set the Foxes on a successful route.
Arsenal was out at bay by Kasper Schmeichel and Leicester's valiant defensive unit, only for Welbeck, making his first appearance since April 2015, to strike deep into stoppage time.
Arsenal is now in the second spot, which is above north London rivals Tottenham and that too within two points of leaders Leicester.
To discuss in particular, Arsene Wenger made two changes to the Arsenal side fielded at Bournemouth, after injured Gabriel was replaced by Per Mertesacker and Mathieu Flamini making way for Francis Coquelin.
Since November, Francis Coquelin started his first Premier League, while Leicester were unchanged from the side that comprehensively beat Manchester City, recently.
Arsenal had a grand start as Alex Oxlade-Chamberlain was played in behind the Leicester defence, but Simpson was on hand to clear before the right-back forced Alexis Sanchez to head the resulting corner wide inside, 2 minutes.
Oxlade-Chamberlain’s involvement was observed again after as his chipped pass appeared to strike N'Golo Kante's arm, but referee Martin Atkinson was unmoved.
Before the game sprung into life, a cagey opening 10 minutes passed, as both sides exchanged blows in search of an opener.
Firstly, Christian Fuchs played Shinji Okazaki through on goal, only for the offside flag to deny the striker. Aaron Ramsey was then played well, prompting Schmeichel to race off his line on 15 minutes to intervene, before Petr Cech produced a brilliant save, to keep out Vardy's low header, after a minute.
Leicester captain Wes Morgan then denied Olivier Giroud and Sanchez, after he threw played well shotting twice in the space of five minutes, before Giroud's 31st-minute header was ruled out for offside.
As Vardy ended a brisk counter by drawing Nacho Monreal into a rash challenge, the Foxes took advantage of their reprieve. The challenge left Atkinson with no choice but to award the spot-kick.
The England striker dusted himself down and rattled the ball home from 12 yards, turning it as the 19th Premier League goal of the season.
Due to the injury, at half-time, Arsenal were forced to replace Laurent Koscielny, but that failed to prevent Arsenal from flying out of the traps when played resumed, with Ramsey dragging an early shot wide.
After Monreal brought Riyad Mahrez to ground, Atkinson waved the claims away. After Simpson picked up two yellow cards in quick succession (second card for bringing Giroud to ground), the game swung in Arsenal's favour.
Mahrez was sacrificed as Leicester battened down the hatches, and Arsenal's pressure soon told as Walcott rifled home superbly after Giroud's fine knock-down in the area.
Even though, Arsenal continued to throw bodies forward against a tiring Leicester team, Schmeichel could not prove penetrable.
After undergoing knee surgery, Wellbeck was brought off the bench to make his first appearance of the season. This initiative proved to be a comeback to remember for the England international, as his deft flicked header saw the Gunners finally beat Schmeichel with the last kick of the game.
Arsenal: Cech (6), Bellerin (6), Mertesacker (6), Koscielny (5), Monreal (5), Coquelin (5), Ramsey (6), Oxlade-Chamberlin (6), Ozil (6), Alexis (7), Giroud (7).
Used subs: Chambers (7), Welbeck (8), Walcott (8)
Leicester: Schmeichel (9), Simpson (5), Morgan (7), Huth (7), Fuchs (6), Mahrez (6), Kante (9), Drinkwater (8), Albrighton (7), Okazaki (7), Vardy (8).
Used subs: King (5), Gray (6), Wasilewski (5).
Man of the Match: N'Golo Kante.
By Phani Ch