I did want to see Young and Di Maria before because I felt we could hurt Liverpool on the counter, but the more I think about it, I actually feel, given the right players, we could boss the game (well not boss it, but have more possession), and Mata is someone you put in to help you keep the ball, especially under the press Liverpool will put us under.
However, I've noticed that Liverpool only press from last third/middle third of the pitch of the oppositions half, then when it gets into their half, they kind of let the opposition have the ball, and if they win it, that's when they counter. That's my only worry - the counter, and how Mata will cope getting back, but I think he'll be fine.
People say Spurs were poor the other day, but when they had the ball, as Van Gaal said, we set up in a 4141, made ourselves narrow and compact, and made it very hard for Spurs to find pockets of space, thus forcing them to go wide.
I'm quietly confident for this game, despite Liverpool's good run of form.