James Spencer`s strike eight minutes from time handed the Shrimps the points and put a dent in the Millers` play-off ambitions.
"There was a distinct lack of confidence and that is quite strange and I`m at a loss to explain it," Liddell said.
"Even though we got beat on Tuesday, we didn't play poorly, but in this game we played poorly.
"There was a lack of quality out there from both teams. We made too many mistakes and eight, nine, 10 of our players didn't play very well.
"You know when you have played poorly and the players know it, and yet we`ve still got a chance. We are still only seven points off a promotion place and two points off the play-offs, but if we play like that we are not going to get where we want to be."
Source: PA