A triple second-half strike inside 37 minutes either side of the hour ruthlessly cut down battling County at the foot of the biting cold Pennines writes Tony Rees.
Josh Hawkes' double and a goal from Oldham substitute Joe Quigley sent the Exiles spinning to defeat - as new Port boss Christian Fuchs gazed on, no doubt now analysing the the size of the task that unfolds for him between this chilled autumn and the warm sunlight next spring.
Leicester Premier League title winner Fuchs will take heart from a first-half display that saw his men stretch the hosts, indeed the uplifting displays from Bobby Kamwa, Sammy Braybrooke, and skipper Lee Jenkins were noteworthy.
But the Exiles were badly mauled as the Latics cut lose after the break, taking full advantage of the plethora of openings carved, as the Port fought frantically to stem the most relentless of attacking tide at Boundary Park.
Fuchs had tweaked his formation and shuffled his options for the arduous trip north. County switched to a flat back-four, moving versatile Cameron Evans into a central midfield holding role, partnering the on-loan Leicester youngster Braybrooke. Wideman Kamwa returned, as did playmaker Kai Whitmore, after serving a one-match suspension.
The Latics, astonishingly without a home League win for over two months, made just the one alteration to the line-up held to a goal-less draw by Crewe seven days earlier - defensive midfielder Ryan Woods replacing Kai Payne, who dropped to the bench.
Exiles chief Fuchs, having only a solitary training session with his troops since being appointed 48 hours ago, would have known the hosts ship goals regularly in the opening 10 minutes of a clash, although Oldham boast the meanest rear guard in the section.
It was Twentieth Century artist LS Lowry who glorified the industrial grit of this corner of the Saddleworth Parish. There was little doubt former Austria international skipper Fuchs would need County to mix a similar and curious cocktail of reality with that vital twist of enterprise.
The blonde-haired Braybooke was Picasso-like, as he daubed multi-angled passes around - Oldham retreating with a high degree of alarm. Kamwa turned Jamie Robson to flash a drive across goal on five minutes -Committed Newport moving forward again on the half-hour, Courtney Baker-Richardson's blast cannoning off Manny Monte with the Latics swaying.
With Fuchs barking out instructions from the edge of his technical area, County were now roaring. Braybrook's set piece was met by the leaping Jenkins - the centre-back's downward header just clawed clear by keeper Matt Hudson.
Exiles skipper Jenkins was, initially with Akin Odimayo, holding the Amber line in resolute fashion, but the visitors needed to be vigilant as the Latics crept back into a fascinating contest. Robson saw his cross scream across a gaping goal with Joe Garner stretching to make contact, Hawkes previously extending County gloveman Jordan Wright low to his left.
But battling County's foundations did finally splinter on 53 minutes. Wright turned away Michael Mellon's initial effort, but loitering Hawkes gleefully smashed home his angled drive emphatically.
It was a withering blow for the Exiles who continued to graft intensely as temperatures dipped in the stadium. Substitute Michael Spellman lifted a difficult opportunity over the bar, Newport counting the cost of that miss as Latics striker Quigley received from fellow substitute Kane Drummond before netting 16 minutes from the death.
With the clock moving onto 90 minutes, worst was to come as menacing Hawkes pulled wide before sending a low drive wide of Wright's left hand to inflict even more agony on Newport's hardy 222 travelling fans housed in the upper Caddy End.
Oldham Athletic [4-4-2]
Matt Hudson
Jamie Robson
Manny Monthe
Don Daniels
Jack Caprice
Luke Hannant
Josh Hawkes
Tom Pett
Ryan Woods
Joe Garner
Michael Mellon
Subs
Tom Donaghy [GK]
Kane Drummond for Hannant 46mins
Mike Fondop for Garner 46mins
Dynel Simeu for Daniels 90mins
Kai Payne for Woods 90mins
Joe Quigley for Mellon 70mins
Will Sutton
Newport County [4-4-2]
Jordan Wright
Habeeb Ogunneye
Lee Jenkins [C]
Akin Odimayo
Anthony Glennon
Bobby Kamwa
Cameron Evans
Sammy Braybrooke
Kai Whitmore
Courtney Baker-Richardson
Gerard Garner
Subs
Nik Tzanev [GK]
James Clarke
Ciaran Brennan for Odimayo 31mins
Michael Spellman for Ogunneye 67mins
Michael Reindorf for Kamwa 79mins
Cameron Antwi
Ben Lloyd for Baker-Richardson 79mins
Referee : Andrew Miller
Assistant Referees : Oliver Bickle & Matthew Archibald
Fourth Official : Paul Stonier
Attendance 7056 [222 visiting fans]