2 shite defences up against each other today. Similar attacking dangers when United are at their best, but Arsenal have the edge in both departments. De Gea will have to be on top form, but it's very hard to see anything but 3 points to the Arse. Also, Arsenal have been noted for scoring late goals recently, and United for fading and conceding them.
What should be a good possibility if United are under pressure and when they go behind, is a yellow card or 2, and in particular Fellaini getting his comeuppance - he can't get away with continually walking through players - like he did against City with Aguero - and elbowing. Arsenal's tricky players could give him a nightmare and maybe today will be the day when the crowd get on top of the Ref, and we see Fellaini sent off. His luck can't last forever. But then again, he plays for United, so maybe it can.