York City fell to a second straight defeat in the Vanarama National League, beaten by the solitary Kidderminster goal on home turf.
In what was a fairly dull first half, both teams had limited chances, but it was the visitors who came closest right at the end, forcing saves and blocks out of the Minstermen to deny almost certain goals.
They carried the momentum into the second 45, and took advantage of a disjointed City performance, netting the winner scrappily from a set-piece.
Inside the final eight minutes, former York striker Amari Morgan-Smith leapt highest in the box to nod home and haunt his ex-club once more, sending Harriers fans home elated.
Having played a 4-3-3 formation throughout most of the pre-season campaign, York fans were somewhat confused with the change away at Wealdstone last week and remained bewildered by another odd set-up to play Kidderminster - Tyler Cordner, Quevin Castro, Zanda Siziba and Alex Woodyard all came into the side as they were handed their full debuts by manager Michael Morton.
Kiddy boss Russell Penn was forced to make just a single change to his team that played out a goalless draw against Woking on opening day, as Kai Lissimore replaced injured captain Shane Byrne.
Buoyed by the beginning of a brand-new era and an electric home crowd, York City looked for an early breakthrough, and almost had it when new man Quevin Castro was played through, but just couldn't take it past a confident Christian Dibble from a wide angle.
There wasn't a whole lot to talk about in the first twenty minutes, as City showed little signs of promise, and though dominating a lot of the ball, they rarely escaped their own half.
Kidderminster proved why they had been promoted from the National League North, remaining hard to break down and showing glimpses of quality, but could only conjure up a poorly struck half-volley from Zak Brown.
However, it was Kiddy who the best chance so far fell to, as a cross in from the left picked out Christian Oxlade-Chamberlain, who just couldn't manage to find the target, heading narrowly wide.
With the hosts finding little luck inside the box, Levi Andoh found himself breaking forward from his original wing-back position, and bending a fierce effort over the top from 30 yards out.
Nearing the end of the first half, the Minstermen were practically hanging on, as they required a super stop from ex-Premier League 'keeper David Stockdale, and an even better block from Andoh to deny the visitors a couple of certain goals from Amari Morgan-Smith and Brown respectively.
The second half kicked off just like the first closed, with Kiddy looking to cause serious problems inside the opposition box, and they almost did, with a bit of a scramble around the penalty spot that was eventually cleared by York.
An occasional opening for the Minstermen saw Dan Pybus take on a shot from range but his strike was high and wide, the game approaching the hour mark.
It seemed City were starting to get back into the flow of it, Maziar Kouhyar letting fly with a curling effort from the edge of the box, which had Dibble diving at full-stretch.
Eyebrows were raised over the substitution of Castro, having looked a threat attacking-wise, while clubman of the year Olly Dyson entered the fray to some delight.
The midfielder almost had an immediate impact, drilling one hard and low but unfortunately for him, wide of the target.
Dipo Akinyemi, who had been supplied up top throughout the game, managed to ripple the net, but ultimately it was only Dibble's side-netting that was harmed.
Then, with seven minutes to go of the ninety, the opener would arrive, but for Harriers.
It was the same old story from previous years for the North Yorkshire side of conceding from set pieces.
A corner into the mixer saw the ball bounce off a couple of heads, before Amari Morgan-Smith leapt highest to nod past an almost helpless Stockdale, sending the travelling fans into raptures.
With little time remaining, York debut-maker Callum Harriott tried to create some sort of opportunity with a cross, though it was blocked well by a yellow shirt, only as far as Kouhyar, before his fierce half-volley was excellently saved by Dibble.
Seven minutes of added time gave Morton's side a glimpse of hope, but nothing would come from it, as the Minstermen succumbed to a second straight defeat.
For Kidderminster, it was elation, picking up their first three points back in the fifth tier, and continuing their impressive unbeaten run.
York City: Stockdale, Crookes, Cordner, Andoh, Kouhyar, McLaughlin, Pybus, Castro (Dyson 66’), Woodyard (Hurst 83’), Siziba (Harriott 72’), Akinyemi
Subs not used: Campbell, Latty-Fairweather
Yellow cards: McLaughlin (78’), Kouhyar (79’)
Kidderminster Harriers: Dibble, Oxlade-Chamberlain, Knight-Percival, Preston (Penny 90’), Pearce, Richards, Lissimore, Leesley, Hemmings (McNally 73’), Brown (Phillips 59’), Morgan-Smith
Subs not used: Lambert, McDonagh
Goals: Morgan-Smith (83’)
Yellow cards: Leesley (79’), McNally (86’)
Referee: Farai Hallam
Attendance: 4371 (181 away)