Bernd Hoffmann, chairman of the Bundesliga outfit, said on Hamburg's website that Madrid had offered £1.7million plus a friendly match for the 34-year-old striker but the club had rejected the offer 'again and for the last time' on Sunday.
Ruud awakening: Madrid have been warned off Van Nistelrooy (front)
Hoffmann says Hamburg will do everything to secure a place in European competition next season and so it is 'unthinkable' to let Van Nistelrooy go.
Former Manchester United star Van Nistelrooy joined Hamburg from Madrid a year ago. The club are currently sixth in the Bundesliga, 17 points behind leader Borussia Dortmund.
We want you back: Real Madrid fans hold up a Van Nistelrooy shirt during Sunday's La Liga match against Real Mallorca
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