After the first half-hour of this dour game it felt more like an end-of-season contest between two sides with nothing left to play for, but Darlington should have taken the lead long before the deadlock was eventually broken in the 38th minute.
Darlington striker Greg Blundell had the first chance of the game after only six minutes and, although Lincoln responded with a header from striker Mark Stallard in the 17th minute, it was the home side who continued to dominate.
Blundell fired straight at Lincoln keeper Alan Marriott in the 25th minute and defender Mark Phillips also went close in the 32nd minute. And then seconds later Blundell set Julian Joachim on his way and he looked certain to score, but somehow dragged his shot wide of Marriott's goal.
Joachim opened the scoring, however, in the 38th minute when he headed in a Blundell cross from close range for his tenth goal of the season.
The home side almost doubled their advantage a minute into the second period when Rory Prendergast found Neil Wainwright free at the far post, but the winger failed to hit the target with a shot from ten yards.
Lincoln dragged themselves back into the game as Darlington keeper Sam Russell saved from Ryan Amoo in the 54th minute before the visitors grabbed an equaliser in the 76th minute. Evan Horwood needlessly conceded a corner and Lee Beevers headed in his sixth goal of the campaign from Jeff Hughes' flag kick.
As the game went into four minutes of time added on the visitors were denied victory when, firstly, substitute Jamie Forrester saw Russell fingertip his effort over the crossbar and then Darlington defender Patrick Collins hacked the ball off the goal-line after Beevers had headed against the post.
Seconds later, substitute Junior Mendes fired what appeared to be the winner for Lincoln, but the ball failed to cross the line according to referee Nick Jones.