The Red Devils are preparing to travel to Merseyside to take on their bitter local rivals as the old foes come face to face for the first time this season.
United head into the game on the back of their disappointing 1-1 draw with Stoke City before the international break, while Liverpool are aiming to continue their recent good form after their 2-1 win over Swansea.
There is set to be a raucous atmosphere at Anfield as United prepare to travel to Merseyside.
And Smalling admits that he – and especially his new team-mates who do not have much experience of playing against Liverpool – must stay calm during the game.
Speaking in an interview with United’s website, Smalling said: “It’s one of those where the manager has stressed again this week we need to keep our emotions in check because even players who haven’t been at United long know how important this fixture is.
“It’s about controlling our emotions and keeping all our men on the pitch. It’s a game where I think you need to play to your maximum.
“Quite often on the pitch, you’re trying to call to the midfielders to say there is a man there but it’s so loud and the atmosphere is so alive, it’s just your blood flowing through your body that makes it hard to control those emotions.”
Manchester United are currently three points behind their bitter local rivals.
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