Slipped quietly into the arguments promoting the formation of April's doomed European Super League was a suggestion that the Premier League's "Big Six" were all on board. Manchester City, Liverpool, Manchester United, Chelsea, Arsenal and Tottenham Hotspur all signed up for the project that collapsed in a matter of days, as fans across Europe voiced their anger at the sheer arrogance of a plan to sacrifice genuine competition for unprecedented financial gain.

The idea that "founding member clubs" could never be relegated was partly predicated upon the presumption that an impregnable hierarchy already existed in each of the big European leagues. Few could argue that Man City, Liverpool, Man United and Chelsea still stand at the vanguard of Premier League football, but the presence of Arsenal and Tottenham in the Super League's English sextet was palpably based more on pedigree (and let's be frank, revenue) than recent sporting performance.

There was a split among the Premier League clubs along a clear fault line: those whose power and influence were required to give the Super League credibility, and others who felt they couldn't afford to be left behind. The financial effects of COVID-19 are shifting the landscape further still, as certain clubs exploit the vulnerabilities of others to reinforce their position.

So, is it time to redefine or abandon the concept of a "Big Six" entirely?

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It is a moniker that perhaps has its modern-day roots in the inception of the Premier League itself, when the country's leading clubs came together to form a breakaway league, frustrated by the lack of money in the game.

The "Big Five," as they were known in the late-1980s and early-1990s, were Arsenal, Tottenham, Manchester United, Liverpool and Everton. Representatives of this quintet met at a now-infamous secret dinner with then-television-executive Greg Dyke in October 1990, which led to the formation of the Premier League less than two years later.

As the Premier League became a global phenomenon in the years that followed, the Champions League expanded to the extent that by 1999, four teams from the top three leagues (according to UEFA's rankings) were allowed to compete. That didn't happen in England until the Premier League's coefficient was high enough in 2002, and given the revenues on offer from European competition, the top four had strong claims of being the "Big Four" each year.

Those top four spots have been shared by Chelsea, Man City, Liverpool, Man United, Spurs and Arsenal every year since, aside from Leicester City's stunning 2016 title success (an achievement that looks more remarkable with each passing season, it stands as the most wondrous outlier), Everton's fourth-place finish in 2005 and Newcastle United's third in 2003. Roman Abramovich's Chelsea and Sheikh Mansour's Man City gatecrashed that order through expensive takeovers in 2003 and 2008 respectively, essentially buying a seat at the top table with owners who are now well-placed to help offset the impacts on revenues of the coronavirus pandemic.

Given the COVID-19 pandemic, UEFA have relaxed their Financial Fair Play rules by allowing the 2020 and 2021 financial years to be assessed as one period and taking an average of the combined debts over those two years. The wiggle room created by these and other measures has enabled Man City to spend £100 million to sign Jack Grealish from Aston Villa while pursuing an even bigger deal for Tottenham captain Harry Kane. Chelsea have smashed their transfer record to sign Romelu Lukaku from Internazionale for £97.5m, with the Serie A club forced to undergo a firesale resulting from a collapse in revenues over the past year despite winning the league for the first time in a decade.

Manchester United's status as one of the biggest revenue generators in world football is in part founded on ferocious commercial capabilities that have survived relatively well during the pandemic, allowing them to spend £73m on Jadon Sancho and a further £34m on Raphael Varane. Liverpool are yet to enter the market in a meaningful way beyond the £36m acquisition of Ibrahima Konate from RB Leipzig, but they've committed significant sums to wages with long-term contract renewals for Alisson, Fabinho, Trent Alexander-Arnold and Virgil van Dijk, with potentially the biggest extension yet -- Mohamed Salah -- still to come.

These four clubs consequently look best placed to challenge for the 2021-22 Premier League title while the other two members of the "Big Six" are looking to stave off decline.

Spurs continue to face a fight to keep Kane in north London, with head coach Nuno Espirito Santo aiming to halt a decline that began at the end of the Mauricio Pochettino era, and which Jose Mourinho was unable to prevent. Tottenham were among the hardest hit by the pandemic in financial terms, becoming the first club to take advantage of a government scheme that gave them access to a £175m loan from the Bank of England. They had also opened their £1 billion stadium, created to transform their revenues based on live events, less than a year before COVID-19 put a stop to any form of mass gatherings for most of 2020 and beyond.

Cynics pointed out that Spurs' inclusion in the Super League came despite them not winning a trophy of any description since 2008, but they sit ninth in financial experts Deloitte's Money League for revenue generated in the 2019-20 season. (For reference, 11 of the 12 "breakaway" teams were in the top 14 of this particular table, and it would have been a clean sweep had Bayern Munich in third, Paris Saint-Germain in seventh and Borussia Dortmund in 12th all not rejected an invitation to join.)

Significantly, despite the Premier League fulfilling all fixtures during the pandemic -- unlike France's Ligue 1 -- it was not immune to collective financial pain. Deloitte reported in July that the combined European football market contracted by 13% in 2019-20, with a first reduction in revenues since the global financial crash of 2008.

Premier League clubs' revenue also fell for the first time ever from a record of £5.2bn to £4.5bn. More than half of the 20 teams reported an operating loss, and aggregate operating profits declined from £782m to just £55m. Combined pre-tax losses totalled £966m; challengers well below the "Big Six" may feel the top sides are about to disappear further onto the horizon.

Within that group, however, Chelsea and Man City are among the handful of clubs who have sensed an opportunity to strengthen their position by exploiting this slump through their own robust financial reserves. But Spurs are among those trying to stay afloat, with north London rivals Arsenal in a similar boat.

The Gunners are facing a season without European football for the first time in 25 years. They have invested significant sums on upgrading their squad, including £50m on defender Ben White from Brighton & Hove Albion, but are facing a need to generate cash by transferring players out of the club as they enter the final fortnight of the window.

The sheer financial power of the Premier League has created envy among many leading clubs in other countries that, combined with a frustration at UEFA's unwillingness to reshape the Champions League to their greater benefit, led to the pursuit of a Super League in the first place. Only the most naive observers would think that threat is over, even after April's collapsed attempt. But the split between the haves and the have-nots could yet run through England's "Big Six" if the right business decisions are not made in the coming weeks and months.

The Premier League's relatively even distribution of its television revenue continues to help empower others, including West Ham United and Leicester, to break the mould. Both will hope to improve on fifth- and sixth-place finishes, respectively, as for 2020-21 at least, they shook up the "Big Six." Everton also have renewed hope under Rafa Benitez.

Their challenge is to break the top four after a summer in which Man City, Chelsea, Man United and Liverpool have sought to tighten their grip. It is perhaps the enduring appeal of the Premier League that nothing feels certain.