Blind scored United’s second goal as Louis van Gaal’s men wrapped up a 3-1 win over Derby to book their place in the fifth round of the competition.
United have struggled to find consistent form in recent weeks and have only won two of their last 10 Premier League games.
Van Gaal’s side are preparing to host Stoke City at Old Trafford on Tuesday night as they look to improve their form in the top flight.
And Blind has warned that United cannot afford to dwell on their victory over Derby for long as they prepare to take on the Potters next week.
Speaking to United’s website after Friday’s win, Blind said: “Of course a win is always a boost but you have to take it game by game and step by step.
“There is an important game on Tuesday coming up. We have to move on from this and keep the confidence up.”
United are currently five points adrift of the top four in the Premier League.
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