Manchester United will be due a cool £2 million should Ruud van Nistelrooy's Real Madrid win the Spanish title next week.
The deal means Real must pay £500,000 if they win the title and £500,000 more if Van Nistelrooy is Spain's top scorer.
Fergie did a similar deal when he sold David Beckham to Real in 2003.
The small print of Beck's £25m switch entitles United to £1m for the star winning the league.
Now Fergie's clauses are on the verge of being triggered with Real just 90 minutes away from glory.
