Three goals by Sam McMahon, Jason Goodliffe and Kirk Jackson ensured Rovers' possible change in form was short-lived as the Hertfordshire side secured their fourth consecutive victory over Forest Green.
Both sides fought out a scrappy opening ten minutes with Carl Heggs having two chances which were both easy for visiting keeper Mark Westhead to deal with.
Stevenage's best chance came four minutes before half time when McMahon's cross into the Forest Green penalty area ended with Martin Williams firing over the crossbar from five yards out.
On the stroke of half time the visitors went in front from a direct free kick with McMahon's effort from 25 yards finding its way into the top left-hand corner of the Rovers net.
Rovers were unfortunate not to equalise before the hour when Martin Foster's corner found Heggs whose header rattled the crossbar before being collected by the keeper.
Rovers substitute Neil Grayson will feel he should have done better nine minutes before the final whistle when Steve Jenkins' free kick from his own half was flicked on by Kayode Odejayi and Grayson headed wide from seven yards.
Just three minutes later a dreadful headed back pass by Foster forced the Rovers captain to bring down Matt Fisher who was clean through in the penalty area. Foster was shown the red card by the referee and Goodliffe rammed home the penalty.
Stevenage broke again in the 88th minute as a long ball upfield by Jamie Campbell found Jackson who slotted the ball beneath Rovers keeper Steve Perrin into the back of the net.
It was almost four soon after with former Forest Green player Simon Travis saw his effort bounce off the left-hand post after a good run down the right flank