United took the lead inside three minutes when midfielder Sander Berge found space inside the box and beat Boro keeper Zack Steffen with a low shot.
The hosts responded well and drew level in the 14th minute when Chuba Akpom converted Isaiah Jones’ low cross from close range.
A Ryan Giles own goal then put the Blades back ahead before Akpom scored a second with eight minutes remaining.
Here’s how each Boro player fared:
A Ryan Giles own goal then put the Blades back ahead before Akpom scored a second with eight minutes remaining.
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