Jordan Maguire-Drew's second half strike saw Cheltenham Town fall to a third consecutive defeat at Crawley Town's The People's Pension Stadium.
A Friday night trip to West Sussex ended in disappointment as Crawley claimed all three points in a scrappy affair.
Cheltenham did hit the woodwork twice but couldn't find a way past a Crawley side with an outside chance of making this season's play-offs.
The Robins remain firmly in the League Two automatic promotion places as they slipped to a first defeat in April.
There were two good opportunities early on with shots from distance. Conor Thomas' strike after only two minutes went for a corner via a deflection, while Andy Williams' snap-shot almost caught Crawley goalkeeper Glenn Morris out.
Ben Tozer's diagonal pass after the half hour mark was chested down well by Alfie May into the path of Callum Wright who curved a shot wide when working the ball onto his left foot.
The hosts had threatened little, but they had a huge chance to take the lead when Ashley Nadesan was sent in behind from a loose Cheltenham pass, but after getting past Josh Griffiths he couldn't finish into the empty net.
Shortly before half time the best chance of the game fell Cheltenham's way via a former Robins player. Chris Hussey's teasing cross was touched towards goal by former loanee Tom Nichols in an attempt to clear, only to see the woodwork rattled.
After the break Griffiths had to be lively to stop Crawley from taking the lead after they were again gifted the ball. Nichols found himself unexpectedly one-on-one with Griffiths, but the West Brom loanee stood tall and made an excellent stop.
Nadesan poked a later effort wide and Nichols' shot straight at Griffiths was plucked out of the air, while with quarter of an hour to go Sercombe's brilliant chip saw the Robins hit the woodwork for a second time after good pressure.
Failure to hit the back of the net would prove costly, as Crawley clinched their winner through substitute Maguire-Drew.
Nichols fed him with a good pass from a central area on a counter-attack and the Leyton Orient loanee finished low and hard with a shot that went in off the post.
Raglan came close to levelling as Cheltenham tried to hit back but he shot wide from a short free kick.
It was all Michael Duff's side could really produce in an attempt to earn at least a point, as Crawley held on to secure three points.
CRAWLEY: G Morris, A Davies, N Tsaroulla, J Tunnicliffe, J McNerney, S Matthews (T Craig 87), J Tilley (J Maguire-Drew 68), J Hessenthaler, J Powell, A Nadesan, T Nichols.
Subs not used: S Nelson, D Sesay, D Rodari, J Wright
ROBINS: J Griffiths, C Raglan, B Tozer, S Long, M Blair, C Hussey, C Thomas (F Azaz 81), L Sercombe, C Wright (E Chapman 70), A May (S Smith 70), A Williams (I Vassilev 81).
Subs not used: S Flinders, L Freestone, G Lloyd
REFEREE: Sam Purkiss