Sheffield United boss Chris Wilder made no excuses for his team after their 1-0 defeat at QPR.
The Blades were replaced by Wolves at the top of the Sky Bet Championship after Jamal Blackman's early mistake led to a goal for Idrissa Sylla.
On-loan Chelsea keeper Blackman misjudged the bounce of the ball and then dropped it after colliding with team-mate Cameron Carter-Vickers, gifting the waiting Sylla a simple tap-in.
Blackman, who appeared to land awkwardly, was then carried off on a stretcher.
"Our start wasn't the greatest, with the injury to Jamal and the goal, but I just didn't think we deserved anything," Wilder admitted.
"I'm disappointed with my team. We've been out-fought and out-battled and didn't show enough quality.
"We knew that they were going to press and get at us and we needed to show composure, but we didn't.
"We were also sloppy in the second half of the game. It's not been a good night and ended in a deserved defeat.
"It's maybe a little reality check. Everybody's received an enormous amount of praise. I thought we took a backward step tonight."
Wilder was unsure of the extent of Blackman's injury, while George Baldock will also be assessed after going off with a hamstring problem.
"We'll have to wait and see. Obviously it (Blackman's injury) wasn't good," Wilder said.
"It looked a really awkward fall and we'll have to wait for the diagnosis.
"We've not had the best of nights in terms of injuries. Hopefully the news will be OK once we get back to Sheffield and do the necessary scans on both players."