Goals: Heaume 12′; Allen 86′ – Lawley 45+1; Boswell 53′; Metcalf 61′.

Guernsey failed to secure survival on their own terms after a frustrating afternoon against Horsham at Footes Lane.

This defeat, coupled with Chatham’s victory at Chipstead, means the Green Lions have to wait at least another week before they can say with certainty they will be a Ryman South side next year.

It looked so good when Dom Heaume netted at home early on for the second week running, but the Hornets levelled almost on the half-time whistle, turning it round to 3-1 midway through the second half with some excellent finishes.

Substitute Ross Allen gave Tony Vance’s side a lifeline in the final few minutes but Sam Cochrane’s late red card compounded the Sarnians’ misery.

Horsham had started well with Steven Metcalf curling wide after good build-up play and Leroi Riley holding a sweetly-struck free-kick from Scott Kirkwood.

But then the Green Lions grew into the game and showed their intent when a good move led to Craig Young teeing up Dave Rihoy on the edge of the box. But the number seven couldn’t get the ball out from under his feet and his shot trickled wide.

But it would get better just a minute later. The hosts took a quick free-kick and Young chipped in a high floating cross from the left of the area. Just as he did against Carshalton six-weeks previously, Heaume rose highest at the far post to head home.

Tony Nwachukwu came close in the 20th minute after a free-kick had been headed towards the six-yard area, with his acrobatic bicycle kick flying narrowly over.

Midway through the half, a Horsham defender had to be brave in throwing himself in the way of Thomas Dodd’s shot after Young had bundled his way into the area, and then Heaume flicked a header over after really good build-up play involving Jacob Fallaize, Young and Tom De La Mare.

Good goalkeeping by Riley forced Nwachukwu  away from goal before the ball was played back in for Lawley – Young got in the way to make a strong block.

Another good counter-attack from GFC saw Young’s rising shot clear the crossbar after good work by De La Mare and Keanu Marsh.

It looked as though Vance’s side had done enough to see it through until the break, but they were hit with a suckerpunch in stoppage-time as a Hornets counter sliced through the Guernsey midfield and defence. Lawley was played in and calmly slotted the ball under Riley.

The action kept coming as soon as the second half started. Fallaize was well placed to clear off the line from Kirkwood after he had rounded an onrushing Riley, and Cochrane’s header from Ryan-Zico Black’s recycled corner bounced into the grateful arms of Josh Pelling.

The visitors made it 2-1 on 53 minutes as they opted for a short free-kick, in which Darren Boswell was teed up and shot low from 25 yards. The ball found the net past Riley’s outstretched dive via the post.

Pelling made two strong saves to deny Young from the edge of the area in quick succession, and then held a low bouncer from Thomas Dodds.

Those missed opportunities came back to haunt the Green Lions just after the hour. Metcalf was free in the box but there was no disputing the quality of his finish as he curled the ball into the far corner.

Guernsey kept at it though and Alex Duncan almost deflected Rihoy’s cross into his own net, but the ball just evaded the far post.

Riley then made three important blocks, first denying substitute James Thurgar from close range, second saving from Lawley after he had twisted and turned past Cochrane and then tipping over a lovely strike from Kirkwood.

One of the Green Lions’ classic corner routines almost work as Cochrane dummied Rihoy’s pullback but Allen’s shot was blocked in the six-yard box.

It looked as though the Sarnians had run out of steam but hauled themselves back into it when Fallaize rose highest to head down Rihoy’s free-kick and Allen was on hand to forced the ball home from close range.

But that was as good as it got for Guernsey as they struggled to really get going after the break and match the heights of the first half. Thurgar and fellow replacement Alfie Rogers both missed the target – the former firing well wide and the latter’s dipping shot whistling over.

Those chances came after Cochrane was giving his marching orders. Having been booked in the opening minutes for a foul, he was over-enthusiastic as he attempted to get the ball off Nwachukwu, who was holding the ball in the corner, with the referee showing him a second yellow as the Hornets striker went to ground.

Chatham’s win means the gap between us and the drop zone is eight points, with three games to play. One more point should be enough for the Green Lions.

The rest of the Ryman South results were as follows: Chipstead 0-1 Chatham Town, East Grinstead Town 1-4 Ramsgate, Godalming Town 0-2 Faversham Town, Herne Bay 0-0 Dorking Wanderers, Hythe Town 1-1 Whyteleafe, Lewes 2-3 Corinthian-Casuals, Molesey 1-2 Greenwich Borough, Sittingbourne 1-0 Carshalton Athletic, Tooting & Mitcham United 1-0 Three Bridges, Walton Casuals 3-5 Walton Casuals.

Horsham: Joshua Pelling, Alex Duncan, Lewis Hyde (Scott Harris 72′), Jordan Clark, Ashley Jones (c), Charlie Farmer, Steven Metcalf, Scott Kirkwood (Alfie Rogers 78′), Anthony Nwachukwu, Tom Lawley, Darren Boswell (James Thurgar 64′). Not used: Andrew McCarthy.