With the Manchester sides seemingly certain to finish in the top two, the three London clubs are all competing for the two remaining Champions League places. The math does not work cleanly—one club will miss out.
If Arsenal play as they did against Reading for the remainder of the season, they stand a very good chance of edging their way back in to the top four. This was a promising performance with impressive contributions from some surprise sources.
Go to the next slide to discover what we learned from this match.
Arsenal fans are used to seeing Gervinho causing chaos.
However, all too often that chaos has been detrimental to Arsenal's game. Gervinho's erratic running patterns and unpredictable decision-making can make him look like something of a headless chicken.
In this game, however, he was at his devastating best. When Gervinho's confidence is high, his direct running and sheer speed makes him a nightmare for defenders to handle. In this game, he caused exactly the right kind of havoc.
He finished the match with a goal and two assists and will be hopeful of seeing off the challenge of Theo Walcott to keep his spot in the team for the next game with West Brom.
Lukasz Fabianski is unfamiliar with the epithets "calm" and "collected." His Arsenal career to date has been littered with jittery moments. His ability has never been in doubt, but his mentality has long been questioned.
However, he seems to have undergone something of a transformation.
In this match, as against Bayern and Swansea, he was composed throughout. Although his run of clean sheets was ended by Hal Robson-Kanu, Fabianski can still take plenty of credit from another measured display.
On the back of his outstanding displays in Munich and Swansea, many expected Carl Jenkinson to start this game at right-back.
Arsene Wenger's faith in Bacary Sagna, however, remains unwavering.
On the back of this performance it is easy to understand why. Jenkinson is promising but remains raw, while Sagna is one of Europe's most accomplished defenders.
Speculation continues to suggest that Sagna may depart in the summer, but until then he remains very much part of Wenger's plans.
Anyone who saw Alex Oxlade-Chamberlain's slaloming goal against San Marino during the international break will know his confidence is on the rise.
Oxlade-Chamberlain has endured a difficult second season, and his play time has been limited by the good form of his rival Theo Walcott.
However, in recent weeks we've started to see flashes of the talent and promise that so excited Arsenal fans last season.
In this match, his first contribution was a driving run to win a penalty. That kind of contribution could be crucial between now and the end of the season.
Santi Cazorla was at his captivating best against Reading.
His mesmerising display was reminiscent of his dazzling early season form, when he first captured the hearts of English football fans.
It's intriguing that many of his best individual displays have come in the absence of midfield tyro Jack Wilshere.
Both players enjoy occupying the same areas just outside the penalty box. While their combination play can be a joy to watch, they've not yet sufficiently jelled, and for now Cazorla seems to flourish most when Wilshere is on the sidelines.
Santi Cazorla was an unusual signing for Arsene Wenger. Typically, the Frenchman prefers to sign young talent and develop their raw potential.
When he bought Cazorla, Wenger got the finished article. Cazorla was a ready-made world-class player.
His Arsenal form has been excellent and has resulted in increased recognition with the Spanish national team.
With Cazorla's profile in his homeland rising all the time, it surely can't be long until Arsenal are tested by a bid from one of the two Spanish giants, Barcelona and Real Madrid.