Off the pitch, the 2009/10 season will be remembered as the one that the mountain of debt on which the Premier League sits finally claimed its first major victim, triggering a degree of recrimination and scrutiny not seen before in English football's top flight.

The conditions that led to the barely believable phenomenon of Portsmouth, one of 20 clubs in arguably the richest league in the world, flirting with liquidation had been brewing for years. Equally, the ramifications of the chaos at Fratton Park will be felt for a long time. The game in this country may never be the same again.

As I arrived at Old Trafford on Sunday for Manchester United's final match of the season against Stoke, the inherent contradictions at the heart of the Premier League's economy were there for all to see.

The stadium was full to capacity, packed with supporters and football tourists from around the world, many hoping for one final twist in the most exciting title race in years.

The megastore was packed, the club's merchandising operation as healthy as ever. Smartly dressed corporate customers arrived in large numbers for lavish pre-match hospitality. In the TV compound, the league's billion-pound broadcasting deals were in full swing as gigantic mobile galleries beamed live pictures of the action back to millions of armchair spectators in the United Kingdom and around the globe.

A picture of a sport not in recession but in rude health.

But there was anger alongside the intense commercial activity that has made United the world's most valuable club.

Green and gold was everywhere, protesters venting their fury at the £700m of debt the owners, the Glazer family, have now loaded on to United's holding company, and which cost £67m to service last year.

Demonstrators sang violent anti-Glazer chants, unfurled banners and clashed with police as emotions boiled over. Wednesday will mark five years to the day that the club was bought by the Florida-based billionaires and many fans now blame the family for a season that ended in disappointment.

And all the time, the Red Knights watch and wait to make their move. Since I broke the story of the financiers' interest in a takeover of the club back in January, anticipation among the fans has intensified. A bid for the club will almost certainly be made within a month, but the Glazers seem resolute in the face of the hatred.

On a grand scale, the picture at Old Trafford is indicative of many of United's counterparts throughout the Premier League. Thanks largely to a bumper overseas TV deal worth £1.4bn, clubs are generating more money than ever, while attendance figures have held steady in the face of the recession. The problem is not making money but rampant overspending - on wages and the cost of borrowing more.

As with their arch rivals, Liverpool were bought by American investors who borrowed vast amounts to afford the purchase but secured the loans not against their own personal fortunes but against the club itself.

Last week, Liverpool released accounts that revealed the club recorded a £55m loss, the biggest in its history, despite income rising by over £20m last season. Having to pay £40m in interest on borrowings of £350m did the damage, as did £100m in wages.

For the second year running, the club's auditors warned of a "material uncertainty that may cast significant doubt upon the ability to continue as a going concern". Since then, its main lender, RBS, has again come to the rescue with another short-term loan. But, unlike their countrymen down the M62, Tom Hicks and George Gillett have had enough, putting the club up for sale.

What should worry Liverpool fans most is that these figures were recorded in what can only now be regarded as a good year for the club, a year - the 2008/9 campaign - in which they came close to winning the title and reached the quarter-finals of the Champions League.

Since then, Liverpool have gone rapidly backwards, limping home in seventh place in the league and failing to progress past the initial stage of the Champions League, the riches of which they must do without from now on. Martin Broughton, the club's new chairman, insists there is no need to sell assets like Fernando Torres and Steven Gerrard. But, unless a new buyer for the club can be found, it is hard to see how.

Elsewhere, there have been similar examples of financial trauma in the last 12 months. At West Ham, for instance, where administration was avoided thanks only to the intervention of David Gold and David Sullivan, who must still tackle £110m of debt. And at newly relegated Hull, who are £35m in the red. A brutal round of cost-cutting will now be embarked on at both clubs as the sport looks to tighten its belt.



Portsmouth fans are preparing for life in the Championship

Then there is Portsmouth, a club that two years ago were winners of the FA Cup but who today stand as pariahs, an example to the rest of the sport of the dangers of spending way beyond ones means.

Avram Grant's Pompey team can walk out at Wembley this weekend with their heads held high, a last hurrah before the squad is disbanded and sold off in time for next season. But, off the field, Portsmouth remain firmly in disgrace, shamed by the £135m they still owe the taxman, agents, players, clubs, former and current owners, alongside many other more vulnerable, smaller creditors.

The nightmare of Portsmouth reflects badly on the Premier League's fit and proper person test, which raised few alarm bells when Sulaiman al-Fahim, Ali al-Faraj and now Balram Chainrai followed Sacha Gaydamak into Fratton Park.

One of the reasons Ian Watmore felt the need to resign as chief executive of the Football Association was frustration at what he saw as a failure to beef up the rules which allow a man dubbed 'al-Mirage' to buy a club without ever being seen at Fratton Park.

Despite criticism from Uefa president Michel Platini, the Premier League remains loyal to its "liberalism", insisting that Portsmouth's mess is their own fault. That said, it will now vote through a more rigorous screening regime, forcing prospective owners to provide proof of funds and attend meetings before being allowed to buy.

Clubs have had to be more transparent with their finances and prove they are up to date with payments. Hull's accounts are now monitored on a daily basis by the Premier League's experts, while, if required, a club's transfer activity can be controlled and Uefa licenses withheld, as Pompey have discovered.

Meanwhile, Uefa is preparing to phase in its financial fair play rules, regulations that will force clubs to break even to play in the Champions League. The sport appears to be learning from its mistakes. Sadly, at Fratton Park the horse has already bolted.

In contrast, two clubs fortunate enough to be propped up not by banks but by benefactors can look forward to a summer of renewed transfer activity. Roman Abramovich's enthusiasm has no doubt invigorated by Chelsea's title success, while Sheikh Mansour bin Zayed al-Nahyan's appetite will have been whetted by just how close Manchester City came to the hallowed land. Tottenham, fourth spot assured, could be another exception to the general trend of belt-tightening.

Despite relegation, Portsmouth, Hull and Burnley can all look forward to a doubling of the parachute payments for clubs who drop down from the Premier League. If the Football League approves the proposal on Monday, Phil Gartside's dream of a Premier League 2 will move a step closer to creation.

The Bolton chairman has long argued that one of the principal reasons why so many clubs have overspent is the vast financial gulf between the Premier League and Championship. These reforms could go a significant way to levelling out that inequality, albeit at the expense of clubs in Leagues One and Two, who will find it harder than ever to climb through the ranks.

Whatever happened on the pitch this campaign, this was the season when administration, normally limited to clubs in the Football League, came crashing through the walls of Gloucester Place. Now we will discover whether the sport has learned its lesson.