After gaining all three points playing host to Hull last week, it was United's turn to travel to the East coast.
Hull were without a first team fixture so a number of the senior players were selected.
United set out strongly, with Brooke Marsden firing home in the fifth minute to put the Blades 1-0 up.
The game remained tense, with numerous chances for both sides until Jorden Spurr doubled the lead in the 75th minute.
Brooke Marsden then scored her second, and after some excellent individual class Nat Shaw made it a 4-0 result.
Blades: Hall, Ibbotson, Scott, Spurr, Marshall, Brown, Shaw, Csomor, Douglas (Housley 50), Thomas (Wilson, 75), Marsden.