What will be the financial cost for Manchester United of the team's failure at Estadio da Luz? You can take your pick from £2 million (€3 million), £15 million or even, as advanced by one business school professor yesterday, up to £100 million.
The figure of £2 million is irrefutable. It represents the rough cost, in terms of gate receipts and television revenues, of missing out on a two-legged round-of-16 Champions League tie. The £15 million hit relates to potential lost revenues from the competition "gravy train". The train, though, rolls at full steam only for clubs that advance to the final stages - and £15 million is what the winners would expect to collect.
Unsurprisingly, advisers to the Glazers were stressing yesterday that neither figure is remotely large enough to create a financial black hole.
"You have to appreciate that the family are in it for the long term," said one. "One disappointing result will not affect their long-term plans, given they have invested £300 million of their own money in United.
"Look, they have been investors in Manchester United for three years and they have owned the Tampa Bay Buccaneers for 10 years. They are not amateur pygmies who know nothing about sport. They are fully aware that investing in sport is about the rough as well as the smooth. If they wanted to invest in something more predictable in the short term they would have invested in water or electricity stocks."
It is the potential damage to United as a brand that will be of more concern and the Glazers may soon be able to measure any repercussions. Talks to secure a shirt sponsor to replace Vodafone are already well advanced and the Glazers will have a reasonably firm estimate of the sum they should be able to achieve. They have already said they expect more than the annual £9 million Vodafone were paying but how much more and whether it will be dented by the Benfica result have yet to be seen. Anything less than Chelsea's deal with Samsung - thought to be £11-12 million a year - would be a public-relations disaster that could lower the value of the United brand.
"The sustained and continued presence in the Champions League, especially in the later stages, has helped the big clubs to drive up the value of their sponsorship deals," says Oliver Butler of the sports marketing consultants Sport + Markt.
United are not the only club looking for a new sponsor. Milan, Liverpool and Barcelona are thought to be similarly placed and all sailed through to the last 16 of the Champions League as group winners.
In the medium term, though, Chelsea represent the main financial headache for United and the Glazers.
"The biggest concern is that the route into the Champions League is squeezed," says Butler. "It's now more difficult to get in. Basically, Chelsea are number one and there are three more places to go for - only one of them automatic."
United, second in the Premiership, occupy the second automatic berth to qualify for next year. Preserving that position is now a financial imperative and, barring disasters, the Glazers appear to trust Alex Ferguson to deliver come May.
The close season, however, is another story. It is becoming clear the Glazers were planning a major overhaul at Old Trafford next summer. They had always regarded their first season of ownership as one of looking and learning.
The gloves will come off next June, though. A top-to-bottom review is likely to encompass all areas where the Glazers feel United have been punching below their weight, notably revenues from overseas merchandising and what their advisers insist on calling "match-day entertainment" - what the fans spend beyond their tickets.
On this long list of reforms the identity of the manager is now clearly the top item. For Ferguson it is bad news: the signs from the Glazer camp give no reason to suppose he will be excluded from the summer stocktaking.
