Said it earlier but I think they just make the 4th place for three reasons : Mata will get them some extra points they wouldnt get with Young/Nani/Kagawa, Mata's signing will certainly give them some energy/push/fresh ideas maybe like Ozil at Arsenal, while Spurs/Pool simply will crumble sooner or later they lose Suarez maybe ad its over for them, while Spurs still have EL to play.
Next 3 rounds is also crucial, if RVP/Rooney is back from injury and Mata starts to play, its hard to imagine they wont get around 9 points from Cardiff, Stoke, Fulham games.
And while they have these easier games their top four rivals will have: Pool-Everton derby, Spurs-City, Spurs-Everton, Liverpool-Arsenal, I mean their rivals will drop points probably left and right...
For me it seems a huge chance for them the close the current 6 point gap.
Pool made a mistkae not getting anyone in January giving them something extra, they wanted Salah from Basel was close to him then he ended up at Chelsea, now if their is no plan B for them, that's like ohh we can do it even without Salah that will comeback to bite them. Also Gerrard playing way too deep is another bad idea from Rodgers, would like if they could keep their 6 points lead but cat see it.
While I trust Spurs even less, I just dont rate Sherwood but he is pretty unknow as a manager vould surprise everybody but they really dont have a well gelled team.
But if United even drops just another 4-5 points from these Cardiff, Stoke, Fulham games coming up they will then find it extremely hard because their rivals now will drop points vs each other, its a big chance for Moyes. Would be piss funny to see him struggle vs ex-United guys like Solskjaer, Hughes, and even at Fulham Meulensteen he fired the summer.
:D