The Red Devils are two points behind their derby rivals Manchester City after a 3-0 victory over top-four chasing Tottenham Hotspur at Old Trafford on Sunday.
Louis van Gaal’s side face a tough assignment at Anfield this weekend as the Red Devils take on Liverpool, who are just two points behind the 20-time English champions.
United centre-half Smalling is predicting a very open race for the final Champions League qualifying spots in the final months of the season.
Smalling told United’s website: “It is all very close.
“There is only a point between us and Arsenal, and I think it’s very open all the way up to second place, so we will be aiming for that, especially when we are playing those teams coming up.
“We want Champions League football back here at Old Trafford. It’s a must. Fourth is the minimum but when it’s there, second is a realistic target and if we keep on performing like we did against Tottenham then I don’t see why we can’t give it a good push.”
Liverpool kept pace with their top-four chasing rivals thanks to a 1-0 win at Swansea City on Monday night.
The Reds can hoist themselves above the 20-time English champions with victory on Merseyside on Sunday afternoon.
United still have to face local rivals Manchester City, leaders Chelsea, Everton and Arsenal before the end of Van Gaal’s first season in charge at Old Trafford.
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