FBG's team rating page says Marvin Jones vs Arizona is good. (1 Viewer)

[elpollogrande]

I thought Arizona had one of the better defenses. Is it just a positional weakness? Sorry if it's a dumb question, this is my first year doing fantasy.

 

[Hartliner]

Not dumb at all, The number 1 corner will be on the number 1 receiver for Detroit who is Tate. So Jones will have second best corner. I expect Detroit to be down in this match and so Stafford will need to throw in order to keep up in the game. Best WR for long deep passes is M. Jones. He's healthy now and last year lit it up the first couple of weeks. He's a speed guy. If he does really well this game try to trade up to a better receiver you like, to optimize any success he may have early.

 

[dagman]

No, I think your question is valid because I too would have thought Jones would have been at best a Neutral matchup against the Cards, so it must be as you and Hartliner suggested.... a positional weakness. 
I'd have to see your other potential matchups, but perhaps this is just the best one they saw for your team this week.

Here's mine:
https://forums.footballguys.com/forum/topic/760011-am-i-contender-draft-rating/