An own-goal from Mat Sadler before half-time and a header from Franck Moussa gave the Sky Blues a commanding two-goal lead, before late strikes from substitute Jamie Proctor and Andy Drury secured a deserved point for the Reds.
"I am disappointed after being 2-0 up with 10 minutes to go," said Pressley.
"I thought we were excellent in the first half and passed the ball really well especially when you consider that we had no recognised striker on the pitch.
"In the second half we didn't pass with the same kind of consistency and they came back into the game.
"The one point I made to the players was that despite the circumstances was that there is always a way to win a game and, at 2-0, I thought we had found a way.
"But one individual switched off after we went 2-0 up and didn't do their job from a throw-in. He has let his team-mates down and we can't afford to do that - especially after we worked so hard to get in a strong position."