Swindon surrendered top spot in League Two as they suffered their first home defeat since September by going down 2-0 to Forest Green.
Goals from Matthew Stevens and Ebou Adams fired Rovers to an unlikely victory to revive their hopes of an end-of-season push for a play-off place.
Stevens stunned the County Ground into silence by opening the scoring from close range after only five minutes.
Adams doubled the visitors' lead five minutes into the second half when he headed in a Chris Stokes cross.
Swindon were unlucky not to have something to celebrate as in the first half Jerry Yates had a shot cleared off the line by Stokes.
Keshi Anderson also struck the crossbar with a drive from distance in first-half stoppage time.
Two minutes after the second goal, Yates then hit the post with an acrobatic effort after being teed up by Michael Doughty.