Arsenal 2 Leicester City 1

Substitute Danny Welbeck celebrated his comeback with a dramatic last-gasp winner as Arsenal beat the Premier League leaders to revitalise their own title dreams.

Welbeck – who had not featured for the first team in 10 months due to injury – headed in Mesut Ozil’s free-kick with virtually the last move of the game to clinch a crucial three points for the Gunners.

Leicester – who remain two points ahead of Arsene Wenger’s side – had gone ahead through Jamie Vardy’s penalty, but they then had Danny Simpson sent off and Theo Walcott levelled before Welbeck’s fairytale header in the fourth minute of added time.

The onus was on Arsenal to attack the league leaders from the off and they did just that, with Alexis Sanchez getting up to head a corner just wide of the far post.

But the Foxes successfully soaked up that early pressure and began to threaten on the counter-attack – best epitomised by an opportunity for Vardy after 15 minutes.

Kasper Schmeichel hared out of goal to deal with a break from Aaron Ramsey and Leicester immediately switched to attack mode, with Marc Albrighton’s cross picking out Vardy for a header that was stopped low on the line by the diving Petr Cech.

The energetic N’Golo Kante went close, winning possession deep inside his own territory and sprinting upfield to collect the return before curling a shot towards the top corner that Cech scrambled away.

At the other end, Olivier Giroud nodded a corner over the bar and then another header that sailed beyond Schmeichel was ruled void because the striker had strayed offside.

But it was Leicester who made the breakthrough a minute before half-time as Kante broke again and fed Vardy, who was tripped inside the box by Nacho Monreal and got up to slot home the resulting penalty.

Riyad Mahrez looked fortunate not to be booked for a dive when Monreal made minimal, if any contact with him shortly after the restart – but team-mate Simpson was not so lucky.

The Leicester right-back was dismissed after a clumsy tussle with Giroud at a throw-in – his second yellow card within a matter of minutes and ironically, a less serious offence than many overlooked by referee Martin Atkinson.

The Gunners pressed for an equaliser against Leicester’s 10 men, with Ramsey and Giroud both going close – but still not a single save was required from Schmeichel.

Yet the Leicester keeper was finally beaten 20 minutes from time when Giroud headed down Hector Bellerin’s cross into the path of Walcott, who slid a crisp half-volley into the net.

Numerous opportunities for an Arsenal winner went begging as Sanchez uncharacteristically miscued two shots at goal, Ramsey also shanked a drive wide and Giroud was denied by Schmeichel.

Per Mertesacker’s glancing header from a Mesut Ozil cross drifted agonisingly past the upright – but there was still time for another Ozil delivery to hand Welbeck his moment of glory.

Arsenal: Cech; Bellerin, Mertesacker, Koscielny (Chambers 45), Monreal; Ramsey, Coquelin (Walcott 61); Oxlade-Chamberlain (Welbeck 83), Ozil, Sanchez; Giroud.