A Billionaire Bought a Chunk of Manchester United. Now He Has to Fix It.

The process was six months old and already starting to wear on Jim Ratcliffe, the British billionaire, the first time he brought out the Champagne to toast his purchase of Manchester United. But even that celebration, at the Monaco Grand Prix in May, proved premature.

There was no deal. Not yet.

Doing one was never going to be easy. Mostly, that was because any potential sale for United offered a tantalizing marriage of money, power and history: Mr. Ratcliffe, the wealthy chairman of INEOS, the petrochemicals giant, had supported Manchester United since he was boy. United, the most decorated club in English soccer, was one of the most iconic brands in global sports. And the Premier League, to which it belonged, was the richest soccer league in the world.

What ensued was an auction as unpredictable and chaotic as some of Manchester United’s most memorable games. The news media breathlessly tracked surges of momentum between Mr. Ratcliffe’s bid and a rival one led by a little-known Qatari sheikh.

United fans, eager to see their club shake off its unpopular owners, the Florida-based Glazer family, devoured it all. Yet while the negotiations produced months of headlines, discussion and whispers, what they did not produce was a sale.

Mr. Ratcliffe won out in the end. Kind of.

On Dec. 26, the Glazers announced that they had agreed to sell 25 percent of United to Mr. Ratcliffe, one of the world’s richest men. The price — more than $1.5 billion — bought a curious arrangement in which Mr. Ratcliffe, the new minority owner, would take over day-to-day control of the club’s soccer operation. The deal was ratified on Tuesday night.

On Wednesday, as Mr. Ratcliffe outlined his vision, newspapers and websites grabbed eagerly at the headline-ready quotes about new players, old rivals and stadium plans. But a closer listen to his words suggested that the grueling sales process might have been the easy part. Reviving United — a trophy-winning machine a decade ago, in recent seasons reduced to something closer to a punchline — is likely to be a yearslong process, he warned.