Kevin Nolan says the manner of the performance was the biggest disappointment as Notts County suffered a 4-0 defeat to Yeovil Town on Friday.
Alex Fisher scored a hat-trick and Yoann Arquin wrapped the game up as the visitors recorded their first win of the season in emphatic style.
And Nolan says the fact that his team were outworked was the biggest disappointment of all.
“Yeovil showed they wanted it more and that’s why they’ve won,” he said.
“I can deal with losing if we’ve been played off the park but we were out-worked, showed no desire and lost second balls and 50/50s.
“We were not ourselvess and that is totally unacceptable. We cannot put in another performance like that.”
The gaffer says that everything the squad focused on in training this week seemed to go out the window during the game.
He added: “There was so much wrong tonight, which is bizarre because we have worked on a lot of those things.
“None of the things we talked about seem to have sunk in tonight and they’ve struggled under the lights and the expectancy.
“We spoke so much about needing to improve the defending after conceding six in two games but they don’t seem to have taken it on board so we need to drill it into them and get them defending as a unit.”
The players had been scheduled to have a day off training on Saturday but Nolan says that is no longer the case.
He said: “Normally we don’t change the plans but we have to get the players in and make them watch that back so they can learn from it.
“We’ve got to take on the chin whatever anyone throws at us now but we’ve got to stick together and work hard - then we can still get to where we want to be.
“I wouldn’t have them in the building if I didn’t think they were capable of it so now we’ve got to get back to what we did last year and work harder as a team because we looked like individuals tonight.”