Arsenal can win Porto but then the home advantage is what Porto may want to capitalize on to being very defensive because they know that Arsenal in their form earlier is much better than they are, most recently Porto has been performing poorly and I think it's because they maybe reserving their strength for the UCL.

Porto may likely end their UCL journey in this stage because inasmuch as Arsenal isn't I'm their nest form currently they still look better than Porto in form and in them dept except Porto prepare much better and if they are able to secure a win at their he, a draw away wouldn't do any bad the reverse is the case for arsenal, arteta will sure not jeopardize his opportunity to win  the trophy if an opportunity arises for him but then since there is the like of Manchester city and Bayern Munich Arsenal may find it really difficult.