Ethon Archer arrowed in a stunning half-volley as Cheltenham stunned high-flying Swindon 1-0.
The Luton loanee was lurking on the edge of the box and pounced on a poor clearance with a sweet strike from 25 yards which gave Connor Ripley no chance in the 59th minute.
The fast-improving visitors were deserved winners as Swindon failed to match their FA Cup heroics after beating Bolton three days earlier.
From an early corner Hakeeb Adelakun tried his luck at the near post, but Ripley was able to push the ball round the upright.
The Swindon goalkeeper then had to tip a 35-yard inswinger from Luke Young over the bar, while at the other end Aaron Drinan burst past his man before firing a long-range short just wide.
League Two’s top-scorer Drinan was then sent clear but blasted well over.
A glorious Swindon move teed up Ollie Clarke, but he snatched at his shot before at the other end Ripley got across quickly to keep out Young’s free-kick.
Archer finally broke the deadlock in stunning fashion and the goal proved enough to ensure Cheltenham edged a tense derby, leaving Swindon third in the table.
