It’s one of the quirks of our economy that once a commercial enterprise gets big enough, it pretty much takes care of itself. Sure, every now and then you get a Carillion or Lehmann Brothers-type case – the collapse of a bona fide giant – but for the most part, wealth on such a vast scale is effectively self-sustaining: simply being at the top is enough to stay there. Nowhere is this more true than in the world of football. For Lehmann Brothers or Carillion, read Leeds United or Aston Villa: collapses can happen, but are rare exceptions that prove the rule. For the large part, the few clubs at the top of the game have set up fort, raised the drawbridge and are sitting merrily back as the money comes rolling in. While the wider world – and many a lower-league club – sits in the grip of recession-era austerity, football’s fat cats have never had it so good. Chelsea, for instance, have Roman Abramovich to thank for their initial clamber to the top, but nowadays boast the eighth highest revenues of any club in the world (a sum they aim to double over the next decade). In recent years Chelsea have blown £50m on Fernando Torres, £35m on Michy Batshuayi and £56m on Alvaro Morata, who they’re paying £155,000 a week to plod forlornly around up front. But such squanderings are negated, not by Abramovich's fortune but by the club’s broadcasting and marketing income, earned year on year simply by dint of being Chelsea FC. Which brings us, of course, to Manchester United – the world’s highest-earning club, with annual revenues around the £600m mark, and the ultimate example of how, for football’s lucky few, wretched financial wastefulness needn’t be incompatible with staggering commercial success. No club has exploited the endlessly lucrative potential of the Premier League era like United. Under Alex Ferguson, they timed their rise to coincide perfectly with the expansion and globalisation of England’s top division, and rarely missed a chance to monetise their success. That knack has remained – United currently have somewhere between 50 and 70 sponsorship deals – and the club’s alarming post-Fergie tailspin hasn’t prevented them from getting richer each year, buying up the world’s most famous players and handing out the biggest wages in the business. Yet it’s hard to overstate just how badly United have spent their money in the years since Ferguson’s retirement. For starters, the current squad contains four unremarkable bit-parters in Luke Shaw, Juan Mata, Marouane Fellaini and Victor Lindelof, a quartet acquired for just shy of £150m.