Chorley closed the gap at the top of the Evo-Stik League Premier Division to just one point after thrashing table-toppers Skelmersdale United.
A stunning free-kick from Paul Jarvis in the 26th minute gave Chorley the lead before strikes from James Dean and debutant Jack Dorney ensured Chorley had a three-goal advantage at the break.
Skem did hit back early in the second half through skipper Tom Hardwick.
But a late strike from former Skem man Josh Hine sealed a vital three points for the Magpies in front of the biggest Evo-Stik League crowd of the season, as 1,968 supporters packed out the Chorley Group Victory Park Stadium.
The opening 20 minutes belonged to the league leaders as Skem’s fluent football caused the Magpies’ back-line a number of problems.
Dean Astbury saw a shot saved at the far post by Sam Ashton before Darren Stephenson had the first real effort for Chorley as he produced a save from former Magpie Zac Hibbert.
Ashton was involved in the action again as Adam Morning latched on to a Matty Hughes cross but the former’s header was brilliant palmed away by Ashton who was at full stretch diving to his right.
Skem continued to bombard the Chorley goal and Neil Prince was unlucky to see his lobbed effort trickle wide of the post.
But for all the Skem chances, they failed to break the deadlock and in the 26th minute it was the home side who took the lead.
Dorney was tripped on the edge of the area and from the resulting free-kick, Jarvis curled an effort over the wall into the top left-hand corner leaving Hibbert helpess in the Skem goal.
Chorley then had a penalty appeal turned down for handball as Stephenson’s cross appeared to strike the hands of Peter Wylie before the Chorley frontman was involved in the action again, but his effort went wide of the left-hand post.
Keil O’Brien then saw his header tipped wide before Stephenson was bundled over which brought about the second goal.
Jarvis swung in the free-kick from the left flank which O’Brien flicked on to Dean who looped a header over Hibbert to send the Magpies fans wild.
And with the break approaching, Dorney struck.
He received the ball from Stephenson then turned Hardwick before sliding the ball under the keeper to make it 3-0 on 44 minutes.
Ashton produced another fine save from Hughes in the dying moments of the half to ensure Chorley took that lead into the break.
The Chorley keeper was in the thick of the action early in the second half and he was required to palm away a Neil Prince header.
But just minutes later Ashton was helpless in denying Hardwick who was left unmarked at the back post to pull a goal back.
Skem continued to press after there restart and Morning should have done better than head well over from a good position.
Ashton was in action twice in quick succession – the first was a routine save from Astbury, but for the second he received a yellow card after clashing with Morning outside his box.
Many fans and players from the opposition called for Ashton to be sent off, but the referee ruled Chorley had sufficient cover to ensure Ashton stayed on the pitch.
With six minutes remaining, the result was put beyond any doubt when Hine outpaced his former team-mates and slotted the ball in from an acute angle and seal the Chorley win.
Chorley: Ashton, Ross, Cottrell, Teague, O’Brien, Whitham (Vermiglio 89), Dorney, Woolcott, Dean (Roscoe, 86), Stephenson (Hine 71), Jarvis. Subs not used: Walmsley, Grundy (gk)