As the inquest begins after Arsenal's surprise exit from the Capital One Cup, the only question that the fans should be asking is why Arsene Wenger did not pursue the signing of Morgan Schneiderlin during the summer.
The Southampton midfielder played a starring role as Ronald Koeman's side fought back from a goal down to claim a memorable 2-1 win at the Emirates last night, booking their place in the fourth round of the competition at the expense of a much-changed Gunners team.
Wenger was forced to shuffle his pack to avoid risking injury to many of his important senior stars, ahead of this weekend's north London derby against Tottenham Hotspur, but still named a relatively strong starting line-up to face the high-flying Saints.
With Jack Wilshere, Tomas Rosicky, Lukas Podolski, Joel Campbell and Alexis Sanchez occupying the front five positions, the Frenchman also handed a first start to Abou Diaby, deploying the fit-again first-team star in a more defensive midfield position.
The 28-year-old impressed in his 65 minute showing after an 18-month injury lay-off, but it was another Frenchman that drew the majority of plaudits as Schneiderlin set the tone for an upbeat Southampton performance that thoroughly deserved victory by the end of the night.
It was a collectively diligent display by the visitors epitomised by the former Strasbourg star's hard-work in the middle of the park, breaking up play to help protect the back four whilst also serving as a useful link between midfield and attack.
Rise to prominence
Schneiderlin has improved his all-round game significantly since moving to St Mary's for £1.2 million in 2008, growing in stature as the south coast club rose from the depths of League One to establish themselves as a competitive Premier League outfit.
He's always read the game very well and been intelligent in position - boasting an exceptional array of passing - but in the early days the midfielder was viewed as a little lightweight and hesitant in the tackle.
Fast forward six years and that reluctance to roll his sleeves up and stick a boot in seems like a distant memory as Schneiderlin is now a dominant force to be reckoned with, relishing every battle that he's presented with.
It's fair to say that his experience in the lower reaches of English football has been instrumental to his development, producing the finished article that now presents itself in the form of a fully capped international that played at the World Cup in Brazil over the summer.
Schneiderlin's integral role in the current Saints team shows why the south coast club worked so hard to keep him during what was perceived as a player exodus over the summer. Koeman was given the funds to reinvest in his squad, and despite making a number of astute signings the best piece of business could well be retaining the Frenchman's services.
However, that's not to say that the 24-year-old wouldn't have been sold had his valuation been met. Recent history tells us that every player at Southampton has their price, with Schneiderlin's likely to be around the £25 million mark; the same figure the club sold former captain Adam Lallana to Liverpool for, given how highly he is thought of at St Mary's.
Tottenham were the only club that reportedly made a formal bid, with Mauricio Pochettino keen to be reunited with the player at White Hart Lane this season. However, Spurs' £12 million offer was way below the asking price and so a transfer never transpired.
Wenger would probably have been put off by Schneiderlin's price-tag, but there's no reason why Arsenal should not have met Southampton's demands, particularly after paying £16 million to sign his old team-mate Calum Chambers.
The versatile defender is significantly less experienced and hadn't even fully cemented his place in the Saints team, but the Gunners boss saw enough potential in the player to shell out a significant sum on a teenager that made less than 30 first-team appearances during his breakthrough campaign under Pochettino.
With that in mind it makes it even more baffling why Arsenal were put off going for Schneiderlin, especially while they are crying out for a player in that specialist position. It's not like he is old and edging towards the end of his career, either. The best is definitely still to come.
It's true that defensive midfielders don't generally move for big money, but when astronomical sums are being quoted for other less talented and certainly less suitable targets in an already inflated window, the Southampton star seemed like the standout candidate to solve a long-standing problem in Wenger's side.
Search for successor
Mikel Arteta and Mathieu Flamini were only ever going to be stop-gaps until Arsenal acquired a long-term replacement to sit in front of the back four and efficiently sweep up any danger, breaking up play when the team is without the ball and building attacks when back in possession.
With excellent vision, decision-making and passing ability, Schneiderlin has all the attributes to make that role his own at the Emirates and showcased that in exemplary fashion in the League Cup clash again last night.
The marquee signing of Chilean winger Alexis Sanchez from Barcelona understandably prompted excitement from Arsenal fans this summer, but Wenger's failure to recruit a world-class defensive midfielder has let down supporters hoping for domestic success in 2014/15.
Players of that ilk don't generally win you the Premier League title, but the absence of an effective deep-lying specialist can certainly lose it, as the Gunners will find out to the detriment of their aspirations for silverware this season.