Trailing 1-0 with just three minutes left, the Magpies were indebted to two crucial contributions by man-of-the-match Paul Jarvis Who laid on both goals in a dramatic finale which wrecked the visitors’ defiant and prolonged rearguard action.
Alfreton had taken their only real chance midway through the first half to set up the prospect of an unlikely victory.
Poor covering in the home defence allowed Liam Hearn to collect a short forward ball into the box and calmly steer it wide of Ritchie Branagan into the corner of the net.
After that, the Reds erected a solid defensive screen, often with all 11 men behind the ball, which frustrated the Magpies’ best efforts to break through – until those fateful final minutes.
Chorley made the mistake in the first half of pumping forward high balls which the tall Alfreton defenders readily headed clear but the introduction at the break of Robbie McDaid for Marcus Carver contributed to a more measured, ball-to-feet approach which had Alfreton penned in their own half for most of the second period.
The Reds’ keeper Fabian Spiess pulled off a brave save early in the second half, racing off his line to block a fierce shot by Matt Challoner after a clever interchange with Jack Sampson.
Then from a low Jarvis centre Dale Whitham was denied at point-blank range as a defender deflected the ball off the line for a corner.
Alfreton offered little threat in attack, apart from a towering Thomas Allan header at a corner which flew inches too high.
But as the clock ticked down it looked as if the visitors were going to see the game out safely.
Jarvis, however, had still to play his decisive cards.
On 87 minutes, cutting inside, he whipped in a stinging low drive which Spiess could not hold and the opportunist Sampson pounced to fire the loose ball into the roof of the net for his sixth goal in four games.
And in the third minute of added time the Magpies turned one point into three.
Jarvis was again involved, supplying a deep cross from the left which substitute Josh O’Keefe – unmarked at the far post – headed just inside the upright to spark wild celebrations among home fans behind the goal.
The crowd was announced as numbering 999 –Matt Jansen’s men in the end had not needed the emergency services. They had Jarvis.
CHORLEY: Branagan, Challoner, Jarvis, Teague, Charnock (Beesley 80), Jordan, Blakeman, Whitham (O’Keefe 68), Carver (McDaid 45), Sampson, Cottrell. Subs (not used): Roscoe, Azam.