Embarrassed Rotherham caretaker boss Paul Warne admitted he questioned his struggling side's character in the changing room at half time during Saturday's 3-2 FA Cup exit against Oxford.
Oxford progressed to the fourth round with a 3-2 win thanks to goals from former Miller Ryan Taylor, Phil Edwards and substitute Kane Hemmings. Chris Maguire also missed a first half penalty against his former club when the score was goalless.
Danny Ward had fired Rotherham level in the second half before the visitors took control of the tie in the final 10 minutes. Tom Adeyemi's last-minute header proved mere consolation for the hosts.
"They looked sharper and I hate to admit that they looked fitter than us," said Warne.
"I questioned some of the lads' character at half-time. The lads realised they had let themselves down. Some of the individuals underperformed in a big way. They deserved their lead at half-time.
"As good as we were second half it wasn't enough. At 1-1 I honestly believed we were the better team and we were going to win it.
"The second goal was disgusting and I'm embarrassed by it. It's hugely disappointing.
"It was a tough game. We didn't see it as a banana skin or a David and Goliath match. We knew Oxford were a good side and that we are struggling in the Championship so there isn't a massive difference in the standard."
Warne will now look to bring in new players to help the Millers in their seemingly huge task of avoiding Championship relegation, with his side currently 12 points adrift of safety.
He said: "I am thin on numbers. We have let a lot go and everything is being done behind the scenes to get people in.
"We need more options with the position we are in. Apart from me physically driving around and picking people up and putting them in my car there is not much else we can do."