Why would Pogba leave if Man U win the league? Surely, that would give him a reason to stay. I haven't been watching Man U at all so I don't know if he's still playing poorly, fighting with the manager etc.
Locatelli is an obvious fit for us. Would be shocked if we didn't snap him up.
Otherwise I can't think of what holes need filling this market. Maybe another full-back. Frabotta can't be relied upon in big games.