Arsenal have won two of their four Premier League games against teams that started the day top of the table under Mikel Arteta's reign
Arsenal will have known deep down this meeting with Premier League leaders Liverpool had the potential to effectively end their Premier League title challenge - which may explain the wild celebrations that greeted victory.
It may have been too early to declare this a "must-win" match but it was certainly a "must not lose" as defeat would have left Arsenal eight points adrift of a Liverpool team who had lost only one league game on arrival at Emirates Stadium.
And, in the moments after the Gunners unpicked an outstanding first-half's work by gifting Liverpool a farcical equaliser seconds before the break, the audible groans around the stadium and the stunned expressions on the faces of their players suggested old fears were about to be realised again.
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In the first half in particular, Arsenal were more intense than Liverpool, pressed harder than Liverpool, the characteristics that have made Jurgen Klopp's side so feared turned back on themselves.
And yet Arsenal somehow failed to hold the lead. It was the Liverpool fans who were singing during the interval.
Were Arsenal about to be undone by Liverpool again?
Instead, with the stakes so high, Arsenal showed character to overcome the doubts, regroup and - admittedly aided by some abysmal Liverpool defending wrapped up in an abysmal Liverpool performance - place themselves right at the heart of a three-way title pursuit.
Arsenal are two points behind leaders Liverpool with 15 matches to play
Arsenal's joy at the final whistle was unconfined. And why not?
Martin Odegaard grabbed a camera to capture Arsenal's team photographer Stuart MacFarlane revelling in the win, a show of elation that demonstrated exactly what this meant to the Gunners as the Emirates reverberated to the sounds of victory.
Who can blame Odegaard? Some might but this was the biggest moment of Arsenal's season so far, given the price of failure and the reward for success.
Arsenal are now just two points behind Liverpool but the giant shadow in this thrilling title race comes from reigning champions Manchester City, who will go top if they win their two games in hand, starting at Brentford on Monday.
For now, however, Arteta's side will be grateful that demons that could have returned after Bukayo Saka's early strike was levelled up by an own goal via Gabriel's hand, were swiftly banished.
Arsenal were ably assisted by Liverpool's own defensive circus, Virgil van Dijk's failure to deal with a simple long ball compounded by keeper Alisson's injudicious rush from goal and an embarrassing air shot that left the outstanding Gabriel Martinelli with a simple finish.
As the visitors subsided, Ibrahima Konate was sent off for a second yellow card after blocking Kai Havertz while another horrible Alisson blunder allowed Leandro Trossard to sneak a finish through his legs at the near post in stoppage time.
So, when the dust settled, Arsenal had made a significant dent in Liverpool's advantage, renewed hope and optimism replacing the despair that had briefly descended during the interval after Gabriel's calamitous equaliser.
Arsenal's character always comes under the closest scrutiny when viewed through the prism of previous collapses, as it was when they followed up a fine draw at Anfield with a home defeat by West Ham, a tame loss at Fulham and a morale-sapping FA Cup third-round exit to Liverpool at the Emirates.
The response has been exactly what their manager will have demanded, with a 5-0 thrashing of Crystal Palace and a professional 2-1 win at Nottingham Forest. But beating Liverpool, whose only previous league reverse was a hugely contentious loss at Tottenham on 30 September, will arguably mean more than any other win this season given the circumstances, even after beating Manchester City here.
Martinelli was the catalyst with a thrilling performance down Arsenal's left flank, deserving his albeit fortuitous goal for his endeavour, quality and willingness to chase down a cause that looked in Van Dijk's command until he got far too casual.
Arsenal's other outstanding performer was Declan Rice. He has proved on plenty of occasions this season exactly why Arteta was so willing to part with £105m to capture West Ham's captain and this was another one.
Rice barely wasted a pass, was peerless at winning possession and gave the home side an air of midfield authority when they needed it most.
Arsenal have a long way to go in the title race and City will remain favourites - indeed they may have been secretly satisfied at this outcome - but the Gunners delivered with it all on the line so those joyous scenes at the final whistle were perfectly understandable.
The response has been exactly what their manager will have demanded, with a 5-0 thrashing of Crystal Palace and a professional 2-1 win at Nottingham Forest. But beating Liverpool, whose only previous league reverse was a hugely contentious loss at Tottenham on 30 September, will arguably mean more than any other win this season given the circumstances, even after beating Manchester City here.
Martinelli was the catalyst with a thrilling performance down Arsenal's left flank, deserving his albeit fortuitous goal for his endeavour, quality and willingness to chase down a cause that looked in Van Dijk's command until he got far too casual.
Arsenal's other outstanding performer was Declan Rice. He has proved on plenty of occasions this season exactly why Arteta was so willing to part with £105m to capture West Ham's captain and this was another one.
Rice barely wasted a pass, was peerless at winning possession and gave the home side an air of midfield authority when they needed it most.
Arsenal have a long way to go in the title race and City will remain favourites - indeed they may have been secretly satisfied at this outcome - but the Gunners delivered with it all on the line so those joyous scenes at the final whistle were perfectly understandable.