ONE TOO many last night?

Feeling a bit rough? Well, you might want to reach for the Irn Bru and try and clear your head because the greatest football mystery of our time is about to appear on a screen near you.

For football fans it's the preliminary draw for the next World Cup at the glass-lidded Conference Centre overlooking Durban Bay. For the nabobs of Fifa it's something else; the defiant enthronement, against all odds, of Fifa's new general secretary, Jerome Valcke.

It's only 11 months since Valcke was topped, tailed and tormented in a New York court, the judge certifying Fifa officials serial liars. That was Valcke's cv down the toilet. Today is the first day of the new life of Fifa's comeback kid. The mystery is, how did he pull it off?

Bestriding the widest stage you ever saw is Herr Joseph S. Blatter and his new representative on earth, Valcke the debonair snake-oil salesman. What hold does the mendacious Valcke have over the wily Blatter, to prise out of him the game's No 2 job?

General secretary Valke is supervising the draw, 170 countries are taking the television feed. Watch the fond glances between Sepp and Jerome, stare harder as they disengage from each family- of-football embrace.

Yes, there's a helluva back story.

Wind the clock back, it's Spring 2001. The sports marketing company that pays hefty bribes to certain of Fifa's leaders in return for billion-dollar World Cup contracts sinks into insolvency. In the 1990s the ISL company has parted with nearly £20 million in kickbacks. The well is dry.

Along comes Monsieur Valcke and a band of entrepreneurs from the Vivendi company in Paris. They will buy the wreckage of ISL and its dreamy World Cup television and marketing contracts. But, first, due diligence, as the forensic accountants call it, to see what assets are left and how the company got its business.

Valcke and his team look hard at the books, have exchanges behind closed doors with Fifa, then suddenly go home to Paris, leaving ISL to crash. There's never been an explanation of what went wrong.

Recently, an envelope sidled into my letterbox. Inside, a never previously revealed, volcanic letter dispatched by Herr Blatter to Monsieur Valcke, during the negotiations to take over Fifa's contracts. Such violent language.

Terrible threats. Surely, these two could never work together again. But what lay behind the rage?

After the crash I went to the first creditors' meeting in a salon in the city of Zug, cornered the liquidator and secured the easy admission that he had found evidence of dirty money washing around ISL's basement and out to Fifa officials.

The bribes went to offshore companies and accounts connected to some members of Fifa's executive committee. Any trainee accountant would have found the money-trail his first morning excavating ISL.

Did Valcke and his team find the same evidence? How could they not? Everybody in the sports marketing loop knew, had gossiped for years about the screamingly obvious.

So is this what Herr Blatter is referring to in his letter, dated April 30, 2001?

He shrieks at Valcke, "the position of Fifa in no way will ever be altered by any threats or attempts of blackmailing".

Blackmailing? What's going on here? Then Blatter raves about "unacceptable threats" to "certain gentlemen of Fifa". Letter in hand, I called some sources, they said that the French guys had wanted higher commissions on sales than Fifa granted ISL and were piling on pressure to get their way.

With the letter were two internal memos from Fifa's Zurich lawyers to Herr Blatter. They were getting their ears bitten by Alain Gloor, a lawyer for the Frenchmen. If Fifa didn't agree, he warned, his clients owned "a media company which had at its disposal all the resources necessary for presenting events to the world at large".

Were the blazers at Fifa House getting the point? If they didn't concede: "there could ensue extremely serious consequences for both Fifa and certain individuals at Fifa."

Whoar! Were those embarrassing bribes being put into play? Who were these "certain individuals at Fifa?"

The French team talked the talk - then they walked. Blatter set up Fifa's in-house marketing company. Two Christmases passed. Then, mysteriously, Blatter picked Valcke to head it.

Valcke was a disaster. When he misled MasterCard in contract negotiations Fifa had to pay $90m to settle the inevitable lawsuit.

Asked last month if he had ever noticed corruption at Fifa, Valcke said he had never seen any. It was all a mystery to him. I've put in formal requests to Blatter and general secretary Valcke to discuss these blackmail allegations and the mystery of how they got over that nasty spat. They don't want to talk.

More about the marketing bribes will be revealed this spring in a Swiss court when ISL executives stand trial accused of defrauding Fifa of nearly £50m. Many of the valuable rights formerly held by ISL are now owned by the Infront company whose CEO is Philippe Blatter, nephew of the Fifa president. Infront can be found in the same office block once occupied by ISL.

Andrew Jennings is author of FOUL! The Secret World of Fifa: Bribes, Vote-rigging and Ticket Scandals, Harper Sport £8.99.

The Fifa documents referred to in this article can be downloaded at www.transparencyinsport.org