A few years ago, I thought Kaka and Cesc Fabregas were proper heartbreakers...but in hindsight they're a tad too slimy (Fabregas in particular) to be real heart-throbs. David Beckham deserves a mention...but I was thinking mainly currently active footballers. My contenders:

Claudio Marchisio (those eyes! lovely player too)
http://richestcelebrities.org/wp-content/uploads/2014/08/Claudio-Marchisio-Net-Worth.jpg

Mats Hummels (just the right balance of grit and grace)
http://fiestamorelia.mx/fiesta-morelia/uploads/2014/07/mats3.jpg

Xabi Alonso (he's probably only an 8 looks-wise, but his personality compensates for that)
http://s.ndtvimg.com/images/content/2014/aug/806/xabi-alonso-presser.jpg