Can someone explain to me why Juan Monaco is +2.5 to Marty Fish??

[ACoochy]

I dont get it

Monaco rules this guy last 3 occasions (last clash on Hardcourt in march 2012) yet is a +135 dog??

Either im missing something or this is the play.

Cant be North American favouritism shown by books, could it??

Any help here would be appreciated. Thankyou