Bristol Rovers will take a one goal lead advantage into the second leg of the play-off semi-final after a 0-1 win at the New Lawn.
Matty Taylor's 17th minute strike was the only thing to separate the sides with Rovers finishing the game with 10 men after Ellis Harrison was dismissed for a second bookable offence.
Darrell Clarke named an unchanged line-up for the short trip up the M5 after his sides emphatic 7-0 win against Alfreton Town on Saturday.
Rovers started well and Chris Lines had the sides first effort on goal. After a powerful run through the middle of the park he unleashed a shot towards Steve Arnold's goal but he didn't hit the target.
The game had a great tempo in the early going as Sam Wedgbury tried his luck from the edge of the area but couldn't force a save from Will Puddy.
However it was Darrell Clarke's men who took the lead on the 17th minute as Matty Taylor latched onto a loose ball in penalty area, nodded the ball past Arnold and slotted the ball home from what seemed to be a very tight angle for his 20th goal of the season.
Rovers continued to press and a Chris Lines corner was met by the head of Tom Parkes but the defender could only watch as his effort came crashing back off the upright.
The home side were restricted to long range efforts in the first half with a majority of them coming from 25-goal top scorer Jon Parkin but he failed to test Will Puddy one more than one occasion.
Darrell Clarke's men continued to attack in search of a second goal and Ellis Harrison picked out Matty Taylor inside the Forest Green penalty area but Taylor was denied after a fantastic reaction save from Steve Arnold.
Both sides started the second half much more timidly than the first with Matty Taylor and Jon Parkin having speculative efforts for their respective sides.
Matty Taylor did put the ball in the back of the net for a second time but was quickly flagged offside by the linesman to put a premature end all Gasheads celebrations behind Will Puddy's goal.
Forest Green tried the shake things up just past the hour mark bringing on Ollie Norwood but moments later Matty Taylor had a decent effort to make it 0-2 but scuffed his effort wide of the goal.
With just over 10 minutes remaining Ellis Harrison was shown a red card for a second bookable offence following a clash with Forest Green keeper Steve Arnold which left Darrell Clarke's side to last the remaining minutes with 10 men.
The home side piled on the pressure and had a succession of shots on the edge of the area but a wall of blue and white prevented any of them from reaching Will Puddy in the Rovers goal.
Forest Green continued to press and a Charlie Clough header came crashing back off the crossbar deep into injury time before Chris Lines was able to clear moments before the referee blew the final whistle.
The win means Rovers take a slender one goal lead into the second leg of the semi-final at the Memorial Stadium on Sunday (12:45 kick off).
Forest Green: Arnold, Pipe (C), Clough, Bennett, Wedgbury, Fleetwood (Norwood - 64), Racine, Guthrie, Frear (Marwood - 88), Sinclair, Parkin.
Unused Substitutes: Russell (GK), Kamdjo, Coles.
Rovers: Puddy; Lockyer, McChrystal (C), Parkes, Brown; Gosling (Blissett - 81), Mansell (Clarke - 90), Lines, Monkhouse; Taylor , Harrison.
Unused Substitutes: Mildenhall (GK), Leadbitter, Balanta.