He isn't really, because Mata has spent most of his time at Manchester United on the RW. Where he is, in my opinion, not at his best. If we want an upgrade on Mata, we should be signing a proper right winger. Mata is most effective as a 10 but we have hardly used him there. Mkhitaryan is also best as a 10 and at least he seems to be getting time in his best position now. Really, Griezmann would replace Mkhitaryan more so than Mata. The more I think of it, how do you see him as an upgrade on Mata at all? OK - sign Griezmann, play him in his best position which is second striker, which we don't really need and isn't where Matas playing. So play him in his second best position - number 10, again not where we're playing Mata. So who plays on the right wing after he signs? Mata as usual? Mkhitaryan? And who plays on the left? Rashford, who is a striker? Martial, again, a striker? I don't see the signing of Griezmann solving any problems in the final third.