Tomorrow, Arsenal and Chelsea go head-to-head in an all-London clash that could go a long way to deciding the fate of the Premier League's Champions League places for 2012-13. Currently in the driving seat by a clear five points, Arsenal will be looking to bounce back from their shock defeat to Wigan Athletic earlier in the week.
Chelsea, on the other hand, will hope that they can continue to ride their current wave of momentum following impressive semifinal victories over Tottenham Hotspur in the FA Cup and Barcelona in the Champions League.
Both teams face selection dilemmas going into the match, with Arsene Wenger having to decide who can fill his midfield in the injury-enforced absence of the influential Mikel Arteta, while Roberto di Matteo faces a juggling act with the exertions of his men over the past six days and the upcoming second leg against Barcelona to consider.
So which men can sway this fixture the right way for their team in the battle for the Premiership top four?
Needless to say, the Premiership's top scorer and front runner for this season's Player of the Year award will be a key figure in such a big match.
Robin van Persie has been in spectacular form for Arsenal for 18 months now, and is on course to be the first man to score 30 Premier League goals in one season since Cristiano Ronaldo reached the landmark for Manchester United in the 2007-08 season. He is also on course to being the first Arsenal player to do so since Thierry Henry in 2003-04.
Chelsea showed on Wednesday night that they have the defenders to stop top-class forwards, so they will need to repeat that trick at The Emirates tomorrow if they are to stop Arsenal and Van Persie.
The £50 million flop has a long way to go to repay Chelsea for their investment from just over a year ago. There won't be many better opportunities to do that than in this match.
While Didier Drogba has undoubtedly been the form man for Chelsea in their last two matches, the clash at The Emirates could provide Fernando Torres with his big chance. Big performances against Tottenham and Barcelona might mean that Drogba gets a rest for this one, so Torres will need to grab the opportunity with both hands.
A big performance, and perhaps even a winning goal, would push Chelsea's bid for the top four back on course and possibly even boost the Spaniard's chances of making the Spain squad for this summer's European Championships in Poland and Ukraine.
Next to Van Persie, TomáŠ Rosický has been Arsenal's most influential player since their Premier League form was turned on its head following elimination from the Champions League and FA Cup.
The Czech international will carry an even heavier creative burden against Chelsea in the absence of Mikel Arteta and Yossi Benayoun, who is ineligible to play against his parent club.
Rosický's form has been one of the key components of Arsenal's success in the second half of the season. While Van Persie has taken all of the plaudits, Chelsea will have to find a way of stopping Rosický if they want to take all three points.
This young English defender's reputation is growing by the week as he forges his partnership with countryman and captain John Terry. After successfully keeping out Barcelona's plethora of attacking wizardry on Wednesday, Cahill and co. will have to summon a similar performance against Arsenal and their creative talent.
Arguably England's most in-form defender as the build-up to Euro 2012 gathers pace, Cahill, in the absence of David Luiz, will need to continue in the same vein at The Emirates against Van Persie, Theo Walcott and Rosický.
Also posing a goal threat at the opposite end, particularly at set pieces, a big performance from this potential England captain in the making would be a huge thorn in Arsenal's side and a massive boost to Chelsea's Champions League prospects.
As much as is made of Robin van Persie's influence on Arsenal, Thomas Vermaelen is Arsene Wenger's true leader on the pitch. Seemingly the only man around whom the Gunners can build a reliable defence, Vermaelen will need to be at his commanding best to stop whoever plays in attack for Chelsea.
Like Cahill, Vermaelen also provides a genuine goal threat for his team, so Chelsea will need to be aware of him at set pieces.
Arsenal are indisputably a better team with the Belgian in their lineup; it cannot be understated just how important a figure he is for them. A big performance for Arsenal needs a big performance from Vermaelen.
Chelsea's complete transformation since Andre Villas-Boas was dismissed at the beginning of March has been nothing short of astonishing. Roberto di Matteo's promotion to interim manager has coincided with such an upturn in fortunes for the Blues that they suddenly find themselves in contention for two trophies as well as being as close to the top four as they have been all season long.
While a big question must be asked of Chelsea's players in their role in Villas-Boas' departure, it would be disrespectful to Di Matteo to suggest that he hasn't played a significant part in the club's resurgence since that event.
The defensive organisation displayed in Wednesday's victory over Barcelona, as well as the clinical ruthlessness with which Tottenham were dispatched at Wembley, betrays a key feature instilled into Chelsea since the Italian took charge: belief.
Faced with a tricky selection dilemma following a gruelingly challenging week, and with a second leg at the Nou Camp to consider, Di Matteo's role in preparation for this game in particular will go a long way to deciding the fate of Chelsea's Premier League season.
Indeed, while defeat could see the end of Chelsea's challenge to the top four, victory would not only place them back in contention for the top four (and, temporarily at least, actually put them fourth), but it could also pave the way for Di Matteo to take the reins as Roman Abramovich's next permanent managerial appointment.