Chorley collected three precious points at mid-table Ilkeston to stay neck-and-neck with FC United at the top of the NPL Premier Division table.
Both teams have almost identical playing records with the exception that the Mancunians lead by virtue of a single goal advantage.
With the other two top-four contenders – AFC Fylde and Worksop Town – also winning, the Magpies’ success here was simply vital.
A bright start brought Chorley quick reward when after four minutes a Max Cartwright corner curled into the net at the near post.
As the visitors continued to make the running, Josh Hine struck the top of the bar from distance before Chorley went two up after 25 minutes. Hine released James Dean into the box where he was blatantly tripped and got up to make no mistake from the penalty-spot.
But Ilkeston were back in the match on 32 minutes. A corner was headed goalwards from the back of the box and Joe Maguire spun cleverly to whip a shot past Sam Ashton from eight yards.
Chorley began strongly after the break and Dale Whitham should have done better than shoot wide after leaving himself with only keeper Ross Etheridge to beat. At the other end alert anticipation by Ashton prevented Gary Ricketts from fastening onto a through ball which Andy Teague had elected not to clear himself.
The Magpies extended their lead after 67 minutes when a Jake Cottrell cross was headed back into the path of Jack Dorney whose powerful shot took a huge deflection off defender James Reid to completely wrongfoot the helpless Etheridge.
The keeper later pulled off a stunning reflex save to keep out a Dean thunderbolt and Teague was convinced he had prodded a corner well over the Ilkeston goal-line before the ball was scrambled clear.
There was late drama in added time. Dorney, already cautioned, was sent off for a reckless midfield challenge and from the resultant free-kick Mike Williams was given time and room to slip the ball past Ashton from close range and reduce the arrears with virtually the last kick of the game.