Asked what went wrong, McDermott said: "The second half went wrong - we didn't turn up.
"We didn't do the ugly stuff well enough in the second half so I'm very disappointed. It's the first time that's happened with me.
"I've been here many times and know what to expect and you've got to do it for 90 minutes, not 45.
"The second half came as a shock to my system. I'm bitterly disappointed with the players we've got, who are decent but are not at the level at this moment in time.
"If you let runners go at your goal or get the wrong side of players, then that's what happens. I've got no complaints about the result after the second half.
"We need to turn this round as quickly as we possibly can and I have faith in the players they can do it.
"If the fans see another second-half performance like we did then we're going to have a problem. We need to keep the fans with us."
- Sports & Recreation