Danny Wilson said the manner in which his side conceded three goals against Millwall was ‘amateurish.’
The Spireites boss was frustrated by individual errors that allowed the Lions to sail into a 3-0 lead by the interval.
And the amount of chances created by his men was scant consolation.
He said: “I think the manner in which we conceded those three goals we were amateurish at times.
“The first two we’ve tried to play a ball through, they’ve intercepted on two occasions and they’ve hit us at the back. The third goal the ball goes straight over the top of us and we can’t defend against it.
“Being 3-0 down against a team as experienced as the one we’re playing, it’s going to be a difficult task to come back.
“Even up to the first goal I thought we had enough in our locker to win the game, but when you give soft goals away like that you’ve no chance.
“We’ve got to learn a big lesson from that.”
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Wilson felt his men failed to deal with Millwall’s physical challenge and can’t allow other teams to come to the Proact and outmuscle them.
“We have to understand the physicality of this league, you have to face up and go toe to toe with your opponents,” he said.
“In positions today they bullied us and we can’t afford for that to happen because other teams in this league will do the same.
“They’re very organised, well drilled, they get the ball from back to front quickly and you’ve got to defend against that, we didn’t do it.”
Steve Morison was the man taking most of the plaudits after the game and Wilson admitted he was an admirer of the 32-year-old front man.
“I wish he was playing for us,”
“Whether he’s a veteran or whatever you want to call him, he’s showed today how you lead the line.
“We don’t have that type of player at our club but it’s a lesson for the young lads, how he ran in behind us, he never gave up - in the 94th minute he’s still running in at the back of us causing us problems.”
Moving forward, Wilson says hard work is the only remedy to cutting out the kind of mistakes that cost them the game today.
“We had our moments and we had enough moments to win the game.
“One or two things didn’t fall for us but it’s difficult when you’re playing against a 3-0 scoreline, it’s difficult to get that sharpness back again.
“We’ve got to highlight the mistakes and get on the training ground and put it right.
“We don’t want to win two, lose two and draw another one, we want to be more consistent than that.
“We have to do better in our defensive work. We do create chances but we have to defend better, we didn’t look like we were going to get a clean sheet today at all.”