This was the proverbial game of two halves as unbeaten Darlington dominated the opening 45 minutes and could have been three goals up by the interval.
But Steve Thompson's side's never-say-die attitude paid dividends as they grabbed an equaliser four minutes into time added on at the end of a pulsating game.
The home side could have been two goals up in the opening ten minutes but referee Peter Walton disallowed both.
In the sixth minute Darlington striker Tommy Wright slid in to prod the ball over the goalline after a mad scramble in the area, but his effort was disallowed for a foul on County keeper Kevin Pilkington.
Four minutes later Wright's strike partner Pawel Abbott appeared to break the deadlock with a powerful header beyond Pilkington. Again the goal was disallowed with referee Walton judging that Abbott had handled the ball.
In the 14th minute a right-foot shot from Jay Smith was the closest that the visitors had come to a chance of their own and then three minutes later Richard Butcher lobbed the ball over Darlington keeper David Stockdale and onto the roof of the net.
The deadlock was broken five minutes from the interval when Abbott skipped past a couple of weak challenges before laying the ball into the path of the onrushing Wright who side-footed the ball home from inside the area.
Early in the second half Pilkington kept his side in the game when denying Tim Ryan with a superb fingertip save and Butcher was on hand in the 72nd minute to grab an equaliser when firing in from close range after connecting with a low right-wing cross from substitute Andy Parkinson.
The game had a sting or two in its tail however and five minutes from the end Darlington substitute Ian Miller headed in a cross from Neil Wainwright with a goal that looked to have won it.
But there was further drama when, four minutes into time added on, Wainwright lost possession and the ball was quickly swung into the area where Butcher reacted first to fire past Stockdale and earn his side a point.