I think you'll have nothing to worry about here.
We have a poor record against United at the best of times (since we've been back in the Prem, I think the only time we've got a win that I can recall was the famous 5 - 3, where Di Maria scored that beauty, before Vardy ran you ragged and screwed over Rafael) and this squad is crippled with injuries. It's also very mentally fragile (I'm sure I said that on here before the Bournemouth game, but I think that just proves my point) and while we steamrollered a lot of the lower teams earlier in the season, we have bottled nearly every 'big' game this season when the pressure has been on. We've also been pretty awful in the whole of 2020.
However, it's pretty much a cup final, and we'll have had more rest, so I'm not ruling us out completely though; it also doesn't look like you are in great form either.
I think we might get a goal (hopefully Vardy, to cement his golden boot) but really I'd expect you to get two or three. If we go out chasing the game, we're going to lose - Spurs pacy forwards just showed how slow our oil-tanker back-up CB's are. Morgan has been ok, but Bennett has been a liability, and both our full backs are very inexperienced. Our best hope is to set-up shop, try and get one on a break, and then ride it out for the rest of the game.
I'd quite like to score a couple of goals early though, because I'm going to be a nervous wreck.