A Charlie Evans brace secured Town a narrow win over mid-table Harborough at Butlin Road.
The less-than-convincing hosts had to come from behind to record their third victory on the bounce though, with Evans grabbing the game's decisive goal with ten minutes of normal time remaining.
Valley were once more unchanged for the meeting against their relatively near neighbours, and they made a bright enough start when visiting keeper Glen Giles did well to claw away a close range header from Keenah Rosser after just three minutes.
Lewis Rankin volleyed one over and then the same player drew a decent low take from Giles to his free-kick, as the home side continued to push for an early lead.
Rankin went close again shortly after, when he lifted Fazel Koriya's cross from the left just wide of the target. However Rugby let slip their control of the affair, and consequently Harborough twice went close to opening the scoring.
First Callum Milne clipped the base of Matt Hill's post after Callum Steer had picked out Milne's run in behind the Town defence, and then Daniel Forbes nearly punished Hill for not gathering an initial strike from Aaron Preston.
Forbes made no such mistake on eighteen minutes though, when he lifted the ball over Hill after the striker had reacted quickest to the opportunity presented by a flick off the back of Town defender Loyiso Recci's head.
Valley worked hard to get themselves back into the game, but without ever properly troubling Giles in the Harborough goal.
Edwin Ahenkorah did see his shot deflected wide and had a further effort blocked away, before the hosts equalised on the stroke of half time when Liam Francis headed a Rankin corner into the goalmouth - with the ensuing scramble seeing Rosser denied at close quarters before Evans forced the ball over the line.
The restart was immediately followed by a couple of half chances for Evans, before a period of nearly thirty minutes stalemate was played out - with neither side registering a shot between them.
The introductions of Harry Holloway and Simeon Tulloch from the Town bench gave them a boost though, and Evans was soon heading Tulloch's cross wide of the post.
Quick feet from Holloway then created him some space on the edge of the penalty area, and Giles could only parry his well-struck low effort - allowing Evans the opportunity to follow-up and score.
Milne missed a late chance to level things up again when he failed to get any real contact on the ball after he had ghosted in at the far post.
Line-up: Hill; Recci, Francis, Perkins (Holloway); Rosser, Koriya, Summerfield, Bunting, Rankin (Tulloch); Evans, Ahenkorah. Subs not used: Connor, Marsden, Kavanagh. Booked: None.
Harborough line-up: Giles, Bartlett, Gray, Traynor, Williams, Walsh, Steer, Milne, Forbes, Preston, Taylor. Subs: Henbury, Morris, Petranyuk, Zakaria.