Look:
Zaragoza would like, as much more money, as possible,
the ideal situation for them, would be,
Juve to match Real's offer, they would cash in big time,
the player would be happy and they wouldnt have to face Milito as a Real player.
Real knows that either they are buying him from Zaragoza, either they are trading him with Juve, they will have to pay 20+ millions at least, so they might back of,
because there are, other available players at that price.
Juventus want the player, but they dont want to pay a sum near 20+mil,
because there are also available players at this price (Barzagli),
(IMO the wisest thing would be to give Kovac or Tudor + 14mil, but Secco is too dam 4 that)
So we either give more money, or we force Zaragoza to enforce Real...