Chorley claimed local bragging rights over Bamber Bridge after coming out on top of their meeting in the FA Cup third qualifying round tie at the Sir Tom Finney Stadium.
It was a feisty encounter played before a capacity crowd of more than 2,200, with the Magpies’ two-division advantage proving key.
James Dean gave Chorley a 22nd minute lead, one which they doubled just before the hour mark through Tom Smyth’s close-range effort.
Alistair Waddecar halved the deficit in the 67th minute but the visitors scored twice in the last 10 minutes through Josh Hine and the excellent Darren Stephenson.
Brig lost goalkeeper Lee Dovey at half-time, Dovey having been limping since being caught by Andrew Teague in the build-up to Chorley’s opening goal.
He was replaced for the second half by goalkeeper coach Stuart Barton.
Chorley started the game strongly, carving out three decent chances in quick succession.
Hesitancy in the Brig defence let in Stephenson on the right hand side of the box but the No.11 drove his low shot wide of the far post.
Soon after, Jack Dorney got to the byline on the left and pulled the ball back into the middle for Dean to meet and head just wide.
Hine got down the inside-right channel and into the box but his shot went wide of the target.
Brig began to find their feet, playing some decent passing football in the midfield without offering too much of a threat in the final third.
A Paul McKenna corner from the left found the head of Greg Johnstone, the big striker’s looping header kicked clear out of the six-yard box by a covering defender.
Waddecar’s shot on the shot disappeared high over the bar after he had found space on the left of the box.
Chorley broke the deadlock in the 22nd minute in slightly controversial circumstances.
Dovey and Magpies skipper Teague collided heavily as they challenged for a high ball in the box.
With Dovey on the floor having looked to have got the worse of the collision, the ball broke to Dean who drove a low shot into the net.
Both Dovey and Teague needed treatment, with the re-start delayed as the physios did their work.
The hosts responded with Waddecar seeing a shot deflected behind for a corner, then George Bowyer’s low angled shot was gathered by keeper Sam Ashton.
In the run-up to the interval, Hine was only just off target for Chorley with a shot on the half-volley.
Then Stephenson cut inside from the left-wing and drilled a low shot goalwards which Dovey saved well low down to his right.
Dovey was unable to continue after half-time, with Barton replacing him between the posts.
Early in the second half, Barton got himself behind a low shot from Stephenson to save.
McKenna was left limping after being caught on his Achilles by Whitham’s challenge, the former PNE midfielder eventually being forced off.
The Magpies took a stranglehold on the game in the 58th minute when they got their second goal.
Adam Mather whipped over a corner left-footed from the right which Smyth bundled over the line from a couple of yards out.
Stephenson then almost netted a third goal, his glancing header hitting the far post and bouncing out to safety.
Brig got themselves right back in the contest in the 67th minute, Waddecar challenging keeper Ashton for a cross and forcing the ball home from almost on the goal line.
Two minutes later, Stephenson hit the woodwork for a second time.
He checked inside from the left and let fly with a low shot which smacked against the far stick.
In the 77th minute, Waddecar’s corner was met by Paul Alexander, the centre-back’s angled header travelling wide of the far post.
Chorley effectively put the contest to bed with 10 minutes remaining as they caught Brig on the counter-attack.
Dorney got away down the left-wing and had the support of Stephenson and Hine in the middle.
His low centre across the box travelled to Hine who slid in and knock the ball back across Barton and into the corner of the net.
The visitors then got a fourth goal in the 85th minute which perhaps put an unfair gloss on the scoreline.
But it was a deserved goal for the hard-working Stephenson, the winger running clear and rounding Barton before rolling the ball into an empty net.
Bamber Bridge: Dovey (Barton 46), Mahoney, Lawlor, Alexander, Bowyer, McKenna (Marlow 63), Kay, Mullen, Bell, Waddecar, Johnstone. Subs not used: Doughty, Vasey, Reynolds.
Chorley: Ashton, Jacobs, Teague, Smyth, Mather, Roscoe, Whitham (Winter 82), Hine (Mulholland 86), Dorney, Stephenson, Dean (Jarvis 82). Subs not used: Almond, Lynch, Grundy.
Referee: Joseph Johnson (Merseyside)