New England has its best defense in years. The Dolphins have the lowest paid and probably worst offensive line in the league. Ryan Fitzpatrick is a better backup than starting QB and Miami is below average at running back and at the receiver spots. So the Dolphins don't figure to put up many points. 
The Patriots aren't going to show much. There's no need for them to tip their hand against such a weak foe. The Patriots have been double-digit road favorites six times since 2015. The Under has won each team. 
The weather is going to be brutally hot with temperatures reaching the low 100's and high humidity. This is a game the Patriots should be satisfied to sit on a lead and get their reserves in early so as not to risk an injury to a frontline player especially since they already are missing two offensive line starters.