4. Paul Clement's side will be in the relegation battle for the vast majority of this season

It's tough to see the Swans do anything but struggle to remain afloat (no pun intended) all season long. Federico Fernandez's heroic performance kept them in the game today, till Martial, Mkhitaryan, and Pogba turned it on, and the Argentine will have his work cut-out this season.
The Argentine will be hoping Clement sticks to the three-man backline (that included Alfie Mawson and Kyle Bartley) that shut out United for large periods of time, and that may well be their only route for survival - park the bus, as it were, and hope that the pace of Abraham and Ayew along with the ruthlessness of Llorente (when he gets back) gains them points.
They will also need to ensure that when the big boys come to town they don't get hammered - there's nothing that saps confidence like a 4-0 humiliation.