“It looked like two poor teams out there,” said Evans. “I think it was the poorest performance from us that I can remember for a while. If that’s our performance levels it’s not going to be good enough for this league, that’s for sure.
“We look at ourselves and it was disjointed. The central defensive pairing have been a rock to what we have achieved in the last couple of years, but it looked like neither of them had ever played football.
“We will go back on the training ground and work hard and if people think we are going to give up what we fought for last year then there is no chance of that.”
Evans said that some players would be “disgusted” with their showing. He added: “We have got very honest staff and there are some individuals there who would be disgusted by their performance because they are normally very good for us.
“We will analyse some of it, train and get ready for next week. That’s all we can do.”
Birmingham manager Gary Rowett believes his side put in the complete performance.
The visitors twice hit the woodwork before Clayton Donaldson struck the decisive goal on 62 minutes. The away side were good value for the win and created a whole host of chances throughout the game.
They hit a post through Andrew Shinnie and then Dave Cotterill, impressive throughout, cracked the crossbar.
After being in charge for four games, Rowett believes his side are starting to turn around their season.
The win lifted them out of the relegation places and put Rotherham in them.
He said: “I think it was the most complete performance that we’ve had since taking over. I thought we played with really good control and some good composure.
“It was important that when we needed to we picked good opportunities to get into those little spaces.
“We are really pleased with the way we went about things.
“You always worry that maybe a poor performance is round the corner after three games, but I think the fourth one was the best so far.
“They have taken on board every thing that we wanted to do so far. Having a two-week international break helps. We have done some really good fitness and tactical work and that bore some fruit.”
Rotherham United: Collin, Richardson, Morgan, Arnason, Skarz, Taylor (Ledesma 46), Frecklington (Green 67), Smallwood, Pringle, Revell, Clarke-Harris (Bowery 72). Unused substitutes: Broadfoot, Milsom, Derbyshire, Thompson.
Birmingham City: Randolph, Caddis, Morrison, Robinson, Grounds, Gleeson, Davis, Gray (Novak 78), Shinnie (Reilly 88), Cotterill, Donaldson. Unused substitutes: Eardley, Edgar, Shea, Doyle, Arthur.
Referee: D Bond (Lancashire).
Man of the match: D Gray.