Scott Mooney’s stoppage-time winner completed a remarkable comeback for Deeping Rangers.
The Clarets looked down and out as defensive errors left them 3-1 behind at the break.
But centre-half Jonny Clay – who had opened the scoring – claimed a hat-trick of assists in the second-half response.
Following set-pieces, he allowed Scott Coupland and Luke Hunnings to make it 3-3 then Mooney got on the end of another free-kick to provide a dramatic finish.
It was a remarkable way for Rangers to reach the FA Vase third round for only the third time in their history – matching the achievement of 2011-12 and 2014-15 with Tuncay Korkmaz in charge.
After Saturday’s victory, Michael Goode had to accept this was not among Deeping’s top-class displays. Far from it, indeed.
But the result still earns £900 and keeps the Wembley dream alive.
It’s a long road to the final and Rangers can’t afford to repeat those mistakes which could have proved so costly.
They made a perfect start as Clay powerfully headed home Dan Schiavi’s corner.
Within a minute, though, Jack Chandler fired into the bottom corner beyond James Connell on his debut.
The teenager was beaten again by Matt Allan’s effort which took a deflection to go inside the near post.
Despite complaints over offside and handball, Simon Unwin got the final touch in a goalmouth scramble from a corner.
With less than half an hour on the clock, Godmanchester Rovers were 3-1 up.
They looked quicker to the ball and Deeping had no time or space to produce the crisp style of play.
Four minutes after the interval, they got a lifeline.
David Burton-Jones saw a header tipped over following Schiavi’s corner and another set-piece led to a blatant push in Clay’s back.
The defender went down easily but the referee pointed to the spot and Coupland’s 101st goal for Deeping offered real hope of at least forcing extra-time.
Clay’s free-kick from the halfway line was flicked on by Hunnings and the header looped in.
Connell produced a top save from Jos Gwynne which proved more crucial as the game entered stoppage-time.
With two minutes added, Clay knocked the ball into the box again from a free-kick.
It took a bounce and fell perfectly for Mooney who kept calm to lob over Phil Peachey inside the far post.
Three minutes later, it was game over. What a finish and what a fightback!
Deeping didn’t produce anything close to their best – even in the second half when it became pretty desperate.
All that really matters now, though, is a third-round spot.
4-2-3-1: Peachey; C Hyem, Munro, Mackay, Furness; M Hyem (sub King 77 mins), Spark; Chandler (sub Gwynne 72 mins), Unwin, Allan; Yeomans. Subs not used: Dolden, Knight-Percival, Sibanda.
4-4-2: Connell 7; Flack 6, Hunnings 7, Clay 8, Smith 6; Kilbride 6, Dunn 5 (sub Hamilton 54 mins, 6), Burton-Jones 7, Schiavi 7; Mooney 7, Coupland 6. Subs not used: Coulson, Hollist, Marsden, Fisher.
Clay (8 mins, 0-1); Chandler (9 mins, 1-1); Allan (18 mins, 2-1); Unwin (26 mins, 3-1); Coupland pen (50 mins, 3-2); Hunnings (72 mins, 3-3); Mooney (90 mins, 3-4).
Flack, Burton-Jones, Mooney (fouls).
Jonny Clay – the set-piece king. Scored the opener then claimed a hat-trick of second-half assists in the incredible comeback.
Leicester Nirvana (H) – ChromaSport & Trophies United Counties League Premier Division, Saturday.