Andrews says they're well aware of what to expect from United, with both teams chasing European qualification.
"We want to approach this game in a very similar way to how we approach every game," said Andrews.
"We're very aware of their strengths... they've got some magnificent players that we need to try and keep quiet.
"It's an amazing game for us. I said this to the players: we've got three brilliant away games - United, City and Liverpool - and two London derbies at home against West Ham and Crystal Palace.
"We've put ourselves in a good position, but we're not content with where we are and we want to keep pushing."
He added: "(Old Trafford) is a special place to play football, with the history of the stadium and the football club.
"You want to go there and test yourself as a player. And it's a really tough test for us."