John Sheridan watched his side extend their unbeaten pre-season run to three games with a 2-2 draw at Telford on Saturday, July 28.
The Spireites created a number of chances but were unable to put the game to bed and were punished by two sloppy goals.
But the manager wasn't too disheartened with Chesterfield's display.
Speaking to Spireites Player after the final whistle at Telford, he said: “I’ve just said in there that players have got to know their own strengths and each others if they are to go and be successful.
"The main thing, like I said before was fitness, and we’ve had good chances to score more goals today.
"But at the same time, the two goals we conceded were very poor.”
“And that is what you do. This is the best time to make mistakes, two poor goals and they both shouldn’t have happened.
He added: "But if you are going to make them, this is the best time. Hopefully we’ll improve, it’s a tough game against Alfreton and then, the two games where hopefully we’ll get our shape and hopefully be a bit stronger against Huddersfield and Derby.”
Sheridan also revealed that he was keen to add another player to his squad before the start of the season.
He said: "I still think we’re short in areas, I feel as though I need another player. So I’ll look at that and see what I can do and try and strengthen positions I need before the first game.”
Spireites Player subscribers can watch John's interview in full now.