Darlington came back from 3-1 down to secure a valuable point at Northholme.
David Syers pulled a goal back with 15 minutes left, and Quakers threw caution to the wind in the closing stages.
And their enterprise was rewarded in the sixth minute of stoppage time, when Syers seemed to mishit his shot from ten yards past the keeper.
Bartlett was called into action in the second minute, coming off his line to hold a deep free kick from Gainsborough keeper George Willis.
Quakers had a half chance when Stephen Thompson spun quickly off his marker and ran into the box, and tried to pull the ball back for Cartman, but his pass was intercepted.
Quakers took the lead on 11 minutes. Galbraith squared a free kick from inside his own half to Chris Hunter, who launched the ball forward into the area, where Mark Beck outjumped the whole defence as the keeper came out, and the ball landed in the net for his 15thleague goal of the season.
Beck popped up on the line at the other end when he cleared a shot by Chris salt off the line following a corner, but Quakers went down the other end and nearly got a second. Beck’s shot was parried as far as Thompson who drilled the ball across the face of goal, and David Syers, sliding in at the far post, put the ball wide.
But Gainsborough levelled on 34 minutes, when a free kick came over from the right, and Matt Wilson headed past Bartlett, and a minute later Ashley Worsfold ran clear and poked the ball past the stranded keeper.
Quakers hit back, and nearly levelled in a goalmouth scramble, but Cartman’s volley was deflected wide.
Half time Gainsborough 2 Darlington 1
It was 3-1 five minutes after half time, a long throw came in from the right, Chab Chilaka headed against the crossbar, and was first to react to the loose ball.
Quakers nearly pulled a goal back on 54 minutes when Cartman broke down the left and crossed into the middle, where Syers had a shot blocked.
Quakers put two subs on, Gillies and Saunders for Cartman and Thompson
Mark Beck had penalty appeals turned down when he appeared to be held down as he went for a right wing corner, but the ref waved play on.
Arran Wearmouth came on as sub for Liam Marrs on 69 minutes
Quakers got a goal back on 75 minutes, when Gillies crossed into the box, Beck headed towards goal, the ball was blocked but Syers headed in.
Quakers nearly levelled with two minutes left when Syers had a shot blocked, and Falkingham, edge of the area, curled the ball around the keeper, but just wide.
McGovern nearly finished Quakers off wit ha shot on the turn that Bartlett touched around the post.
But Quakers piled forward, and nearly snatched it when Gillies crossed for Saunders to head just wide.
But Quakers levelled in the sixth minute of stoppage time when Falkingham crossed from the left and there was a bit of pinball in the box before Syers managed to knock the ball in, although he seemed to mishit the ball and the keeper was deceived.
Bartlett, Marrs, Ferguson, Turnbull, Hunter, Galbraith, Syers, Falkingham, Beck, Cartman, Thompson
Subs: Gillies, Wilczynski, Wearmouth, Saunders, Burgess
Gainsborough: Willis, Jacklin, Salt, Nyoni, Wilson, Evans, Chippendale, Tempest, Chilaka, Thewlis, Worsfold
Subs: Jarman, Wiles, McGovern, Lacey, Nicholson