Ajax have told Real Madrid that they must meet their €30m asking price for Wesley Sneijder before Wednesday or he will be used in their Champions League qualifier.
The Dutch club laid down the ultimatum after confirming that they have received an offer of €24m for the Dutch international midfielder.
If Sneijder appears for the Amsterdam-based side in the Champions League qualifier in midweek against Slavia Prague then he would be ineligible to play in the competition for Madrid.
"Real have to hurry because we want to play Wesley on Wednesday," coach Henk ten Cate confirmed.
Ajax's technical director, Martin van Geel, was also adamant that the club would not just roll over because Madrid have made their interest official.
"We have a concrete offer of €24m," van Geel said. "We want €30m.
"We are ready to begin the sparring with Real Madrid. We cannot just lie down and accept their first bid."
Despite being previously quoted as believing that Ajax would struggle to win the league if Sneijder left, ten Cate was upbeat about his side's chances.
"Let's not be dramatic," the coach said.
"We should be proud that we have received such a large offer for one of our players.
"Real Madrid are one of the most prestigious clubs in the world and he comes from our youth system.
"If he leaves then another player will be given the chance to rise up.
"That is the way that football is.
"We cannot be weak about this. We still have a great squad and will be one of the favourites to win the title."
