I think it's Carlos Marchena. I've analysed all Spanish players autographs and this one is closest to your one. http://www.nicksportsautographs.com/ebay/pics/Soccer/march8.jpg Your autograph might be different because as you said there was a bunch of people and he was in the rush.
Another thing which says that's Marchena is his number 4, most of the time he played #4. Hope this helps!

Hello,

3 years ago i spent my holidays in Austria and there was the trainingscamp of the Spanish National Team....
The training was over and a lot of people wanted autographs from them and i put the piece of paper into the crowd and sombody signed it..... But i don't know who!

Does anyone know this autograph?

http://s1323.beta.photobucket.com/user/MrMartino/media/DSCN02472_zps124c1475.jpg.html

Greetings from Germany!!! [germany] {up}