Chris Basham was United's hero as he struck a second-half winner to down promotion rivals Leeds, who ended the game with ten men and with defender Pontus Jansson in goal after former Real Madrid goalkeeper Kiko Casilla was sent off for fouling Billy Sharp.
The win sees United leapfrog Leeds and into second going into the international break, and Wilder said: "With the ball we were pretty average and kept turning the ball over pretty easily in the first half, but we grew into the game and showed what we needed to do when we weren't playing at the absolute top of our game.
"After Tuesday [a 2-0 win over Brentford with ten men] a little bit of me was looking to freshen it up because of the amount of effort the boys put in and the distance they covered.
"It's a heavy pitch here and Leeds move you around the pitch, so we had to stick in and we did that."
Wilder also felt the victory, which saw United rack up their seventh clean sheet on the bounce, showed how karma sometimes works in football.
"We've been in the Championship 18 months now and it's maybe balanced itself out a bit," he added.
"The amount of times last season we deserved to win the game and didn't, it must have happened half-a-dozen times.
"A lot of neutrals might have seen Leeds as the better team today but we grew into the game and hung in on there."