Cheltenham suffered a fourth consecutive defeat in all competitions as Rotherham United triumphed 2-0 at Whaddon Road.
The Robins returned to home turf after three successive matches on the road but fell behind when Will Grigg pounced to apply a predatory finish past Scott Flinders after the break.
Rotherham doubled their advantage in the final 15 minutes when Rarmani Edmonds-Green unleashed a sensational low strike from range into the far bottom corner.
Former Rotherham goalkeeper Flinders produced two important saves to thwart Michael Smith and Oliver Rathbone respectively inside the opening 30 minutes.
The visitors successfully utilised the right channel as an attacking outlet and a swinging cross from Sadlier found the head of Smith. Flinders was alert to the danger to palm the ball away and he sprung into action moments later when Rathbone’s shot from range was turned behind.
Cheltenham had their moments with Kyle Joseph blazing wide of the near post and Taylor Perry’s wayward shot failing to hit the target. Michael Duff’s men posed their biggest threat on the counter-attack with the pace of Alfie May and Joseph but failed to translate a series of attacks into an opening goal.
Rotherham took the lead after the break when Grigg scored in back-to-back matches for the Millers. Flinders was unable to handle a shot from the edge of the box and parried the ball to the dangerous Grigg, who made no mistake from close-range.
Flinders was forced into action again when his double-save prevented the Robins from falling further behind. He sprawled to his left to parry a thunderous low shot from Shane Ferguson before returning to his feet to thwart Michael Smith.
Cheltenham had a brighter spell after the hour mark as they looked to catch Rotherham out on the counter-attack. Dylan Barkers, making his first Football League start, slotted the ball down the left for May to latch onto. The Cheltenham forward cut inside but flashed a low zipping shot just wide of the right hand post.
The Millers doubled their advantage with a spectacular strike from range by Edmonds-Green. It was the 22-year-old’s first goal for Rotherham and ended the game as a contest.
Viktor Johansson clawed away Perry’s finish as the midfielder looked to reduce the deficit but Rotherham forward Smith had two chances to extend their lead in the dying stages.
His wayward header was unable to test Flinders, but his final chance, with the final whistle poised, was impressively saved by the 35-year-old goalkeeper.
Cheltenham Town (4-1-3-2): S Flinders; M Blair, S Long, M Pollock, L Freestone; D Barkers; T Perry, C Thomas, L Sercombe (E Chapman 81); A May (C Norton 81), K Joseph (K Vassell 74).
Subs not used: O Evans (GK), G Horton, E Bonds, A Williams.
Rotherham United (3-1-4-2): V Johansson; R Edmonds-Green, R Wood, M Ihiekwe; D Barlaser; K Sadlier, S Ferguson, O Rathbone, B Wiles; M Smith, W Grigg (F Ladapo 77).
Subs not used: J Vickers (GK), W Harding, F Ladapo, C Ogbene, M Miller, J Kayode, H Odoffin.
Attendance: 3,748 (732 away)
Referee: Darren Drysdale