The Championship leaders went down 2-1 at the iPro Stadium on Saturday as Wigan came from behind to claim the points.
After seeing their 10-match unbeaten run come to an end, McClaren believes that the Rams got what they deserved versus the Latics.
"We didn't get going and Wigan came with a game plan and in the end they deserved to win," the former England boss is quoted as saying by BBC Sport.
"I'm not so much angry about the result as the way we played. Credit to Wigan, they stopped us playing and we were too focused on the result rather than putting in a performance."
Derby still lead the Championship table on goal difference ahead of second-placed Watford and third-placed Wolverhampton Wanderers.