zaragoza is favored because its a neutral ground and they are doing a better season than espanyol, also they played their league game on saturday, while espanyol played on sunday. Zaragoza plays for nothing in the league and rested most players, while espanyol fights for not relegating and had to use all the starters, on top of that, with one day less of rest. Zaragoza also has had more time to focus on the match, as they don't have to prepare their league games so seriously. But it's a final.