Chesterfield conceded three goals in the final few minutes to all but mathematically condemn the side to a venture into the National League. Only a miracle to turn round a 19 goal Morecambe goal difference advantage will keep Spireites in the EFL.
Scott Laird opened the scoring but Kristian Dennis equalised from the penalty spot before the break. The killer goal came on 78 when Christian Doidge scored from a break moments after Dennis had almost scored and goals for. Sub Doyle Grubb and a penalty from Doidge, both deep into added time, made for an unflattering score line for the Proact club, proud members of the League since 1921.
Jack Lester made five changes from the side that lost at Exeter City and there was also a switch to a 4-2-3-1 formation. In came Ian Evatt who wore the captain's armband, Drew Talbot, Jak McCourt and midweek scorer Andy Kellett whilst Chris O'Grady, George Smith, Louis Dodds and Sid Nelson were on the bench with Alex Whitmore not involved in the squad.
Forest Green included former Spireite Reece Brown in their starting line up as they looked to build on last weekend's 1-0 win at neighbours Cheltenham Town.
Chesterfield started the game in a lively fashion; McCourt shot wide from a corner, Dennis saw Bradley Collins save well and Kellett hit the post with a shot from just inside the box.
Rovers stepped things up and Laurence Maguire blocked well to deny Brown and Doidge ahead of Dennis miscuing from a great position after Maguire, Talbot and Kellett linked well to set up the chance.
Doidge then saw Aaron Ramsdale make a stunning double save only for the striker to have a third bite only to see his six yard open goal hit the bar.
Defender Laird then opened the scoring before having to make a critical tackle to keep Kellett at bay.
Talbot was fouled by Lee Collins as he burst into the box and Dennis made no mistake from the spot. Dodds came on for Rowley and the sub was soon in the game making a couple of crosses, one which saw a Louis Reed shot blocked whilst Reuben Reid was frustrated by another top drawer Ramsdale save.
The second half started in a cagey manner no doubt the news that both Barnet and Grimsby were ahead at the break filtered through,
Maguire hit a deliberately low free kick to Dennis but the striker, in a good position, slipped on the ball and Rovers cleared but the opening quarter of an hour after the restart lacked any serious goalmouth action.
McCourt whipped in a cross on the hour mark but it just eluded Dennis and Dodds had the ball in the net only for the ref to award a free kick to Forest Green for a foul on the keeper.
Kellett zig-zagged into the area but was crowded out as Spireites upped the tempo, though Maguire had to block a Chris Clements shot and Osbourne over hit a cross as Rovers pushed forwards.
Jacob Brown came on for Robbie Weir with 15 minutes remaining and his first action saw him deliver a superb cross, Dennis half volleyed it but Bradley Collins reacted rapidly to claw the ball away and from his ball out, Rovers fed Doidge in space and he shot low to score on 76.
Kellett forced a save from the home keeper with. 25 yard power blaster and Brown's cross was dealt with well by Rovers rearguard.
O'Grady came on for Evatt and as the fourth official signalled an extra six minutes Brown was denied an equaliser when he hit the post after a burst into the box.
Spireites then conceded two in stoppage time, sub Grubb made it three and Doidge added a penalty after a Talbot foul on Alex Bray leaving Chesterfield hanging by the slenderest of threads, seemingly in an impossible position.
FGR: Collins, Laird, Collins, Doidge, Brown, Gunning, Rawson, Clements, Reid, Hollis, Osbourne. Subs: Belford, Grubb, Simpson, Cooper, Wishart, Campbell, Bray.
Goals: Laird 27, Doidge 78, 90+6 (pen), Bray 90+4'
Chesterfield: Ramsdale, Barry, Evatt, Maguire, Talbot, Weir, Reed, McCourt, Kellett, Rowley, Dennis. Subs: Anyon, O'Grady, Smith, Dodds, Nelson, Hines, Brown.
Goal: Dennis (pen) 36
Ref: Scott Duncan
Bookings: Osbourne, Gunning (FGR)
Attendance: 3336 (662 from Chesterfield)