Rob Roy were made to pay for their profligacy in front of goal as Girvan snatched a dramatic equaliser in the final seconds.
It was a bitterly disappointing end to a game that should have been well wrapped up long before the final whistle and the draw ended up feeling like a defeat.
Rabs started brightly and Gary Carroll’s snap shot in the fourth minute drifted narrowly wide before Danny Boyle headed a Lee Gallacher corner past the Girvan upright.
But the visitors did take the lead in the 14th minute when Kevin Watt fastened onto a long clearance from keeper Steven McNeil and coolly lobbed the ball over the advancing Scott Johnstone.
A minute later Carroll had a shot blocked in a crowded goalmouth. But Girvan came back into contention and Scott Walker did well to clear a Craig Reid cross before, from the resultant corner kick Michael Reilly, headed wide.
Girvan who had the ball in the net in the 39th minute but Reilly’s effort was chalked off for a foul on Gavin Mackie.
Three minutes later a Gallacher drive from 30 yards crashed off the Girvan crossbar with Johnstone well beaten; but from the resultant clearance the Roy were hit with a sucker punch as Robert Patterson latched on to the long ball and lobbed McNeil for the equaliser.
Right on half-time Gallacher freed Watt but his hurried shot went wide and the teams went into the break level.
Just after the break Rabs’ Mackie’s 20-yard free kick flashed past the post.
But it was the home team who took the lead in the 51st minute when Darren Mitchell rose to head a corner past McNeil.
Gallacher’s low drive was taken at the post by Johnstone as Rabs pushed for an equaliser, but at the other end Darren Mitchell sent a free header wide of the target.
On the hour Rob Roy had to replace injured McNeil with their substitute keeper Michael McKinven, but this didn’t affect them too much as, nine minutes later, Watt headed home a Walker cross to bring them level.
Rob Roy increased their dominance; Carroll shot wide and Johnstone did well to punch clear a Shaun Fraser cross under pressure.
But with 12 minutes remaining Rabs grabbed the lead when Carroll connected with a Gallacher cross and headed home at the far post.
In the closing minutes Watt was one on one with the Girvan keeper but shot past the post when it seemed easier to walk the ball home.
Mackie was then brought down just outside the box and he took the resultant free-kick himself, bringing out a parry save from Johnstone and Fraser fired the rebound past.
In stoppage time Fraser should have sealed the points for Rob Roy but when through on goal he put the ball past the post from only a few yards out.
Then came the body blow to the visitors when, with the last contact of the ball, Girvan snatched an equaliser from a corner.
With the Roy defence static, substitute Daniel Cunningham rose like the Girvan lighthouse to bullet a header in to the net and give the home side a point they barely deserved.