The home side came agonisingly close after 19 minutes in what was the first chance of the game.
Julian Alsop's downward header fell to Mark Beesley who turned and sent a low right-footed curling shot which beat the keeper but bounced off the inside of the post before being cleared to safety.
Crawley continued to be pinned back in their own half and were grateful for their keeper Phil Smith being alert nine minutes before half time.
Ryan Williams sent over a cross from the right wing which Alsop again did well to head down and Scott Rogers volleyed towards goal only for Smith to save well.
The second half continued much like the first with Rovers again coming close.
An indirect free-kick was only half cleared by the Crawley defence and this time it was Des Lyttle whose looping volley was deflected just over the crossbar.
Crawley began to get back into the game once Charlie MacDonald had been introduced from the bench, and it was he who set up their goal against the run of play six minutes from time.
A poor goal kick from Steve Perrin went as far as MacDonald which caught out the Forest Green defence and his low drive was well blocked by Perrin only for Maurice Harkin to fire in the rebound.
The visitors lead lasted only a minute as Mark Danks was scythed down in the penalty area by Neil Jenkins and Williams sent the resulting spot kick into the left-hand corner thus giving Rovers a share of the spoils.