When Ricardo Vaz Te struck a late, late Championship play-off final winner for Sam Allardyce's West Ham against Blackpool in 2012, Hammers revelled in victory said at the time to be worth what seemed a massive £90m to them.
The Championship showpiece, the most valuable single sporting fixture in the world, is the ultimate 'sliding doors' occasion, with winning opening up a dreamland of possibilities and defeat leaving little but uncertainty.
It now transpires that West Ham's win seven years ago wasn't worth £90m. It was worth more than 10 times as much, at a tiny bit more than £1 BILLION and counting.
That is the 'additional' income West Ham have made in the Premier League since 2012 - from TV payments, tickets, commercial deals, merchandise and so on - OVER AND ABOVE what they would have made had they spent the intervening period in the second tier.
Only now in 2019 can we say it, but the 2012 Championship play-off final has become the first instalment of this occasion to be worth more than £1bn to the winner.
Of course costs as well as income sky-rocket when you reach the Premier League, so much of the extra money gets spent on transfer fees and wages.
But it can also fund huge infrastructural developments for clubs, and pay off debt, and put clubs on a sounder footing. It is - or can be - transformational.
This jaw-dropping £1bn value on the 2012 win puts into sharp focus the steepness of the stakes as Aston Villa face Derby in this year's match.
The last time Derby won the play-off was in 2007, at a time when victory was said to be worth £60m. Actually for Derby, who last just a year in the Premier League after going up, it turned out to be worth £61.3m.