The popular goalkeeper is set to make his 300th league appearance for the Spireites when they host Shrewsbury Town this weekend.
And he is determined to perform for new boss Danny Wilson after confessing the players have played a big part in the recent slump.
“When a new manager comes in, the players want to try and impress,” he said.
“But if we’re being truthful about things in the last few months, we’ve let two managers down.
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“We’ve got to do all we can now to not let Danny down.
“He’s been at the club before and you can see the passion from the way he spoke to us before the Coventry game and the instructions he gave us.
“We all went on the pitch and tried to show that passion.
“We’ve only been with him a few days so it’s difficult to make comparisons but he knows hat the club is about and he knows hoe to put the smiles onto fans’ faces.
“I’m sure we’ll able be able to do that more in the coming weeks.”
Lee will become only the 17th player in the club’s history to reach the 300 game landmark.
And it will come the day before his 30th birthday.
Wilson is the fifth permanent manager he has worked under after being signed in 2008 by Lee Richardson.
John Sheridan, Paul Cook and Dean Saunders have all managed the Spireites during Lee’s time at the club.
Shrewsbury head to the Proact on Saturday for a crunch clash, sitting two points ahead of Chesterfield in League One.
Wilson will be forced to reshape his defence after Richard Wood was recalled by Rotherham United.
Ian Evatt and Charlie Raglan look likely to miss out with respective ankle and groin injuries, leaving Sam Hird as the only experienced centre half.