Callum Robinson's late goal saw Cardiff City stretch their lead at the top of League One thanks to a deserved victory at promotion rivals Stevenage.
Substitute Robinson broke Stevenage's resistance five minutes from time, controlling the ball outside the area before guiding a half-volley inside the far post from 20 yards to secure Cardiff's fourth successive league win.
Brian Barry-Murphy's team move four points clear of second-placed Bradford City, with Stevenage now three points adrift of the Bantams in sixth.
Alex Revell's team have a game in hand on both clubs currently occupying the automatic promotion places in the third tier, but are left licking wounds having lost a home league fixture for the first time this season.
Stevenage could have few complaints, with Cardiff always looking the more likely winners in a game of few clear-cut opportunities.
Yousef Salech missed Cardiff's best chance of the first half, the in-form striker rising to meet Joel Bagan's cross but heading wide of the far post.
Perry Ng also had a sight of goal when he galloped on to a long ball over the top but dragged a shot across the face, while Joel Colwill fired wide from just outside the area.
The pattern of the contest was similar after the break, with Cardiff more progressive in possession but Stevenage able soak up most of the Welsh side's attacks.
Colwill almost broke the deadlock when he met Bagan's low centre with a side-footed effort which bounced to safety off the bar.
But just as Stevenage – who offered little going forward – began to think a point had been earned, Cardiff found a path to goal.
Omari Kellyman's deflected pass looped to Robinson, who supplied the moment of quality Barry-Murphy had been craving all night.
Stevenage: Marschall, James-Wildin, Houghton, Piergianni, Earley (Patterson 74'), Goode, Freestone, Reid, Thompson (Phillips 59'), Lubala (Campbell 74'), Doherty (Malcolm 87'). Subs Not Used: Ashby-Hammond, Sweeney, Pattenden.
Cardiff City: Trott, Ng, Fish, Chambers, Bagan, Wintle, Robertson (Turnbull 80'), J.Colwill (Kellyman 61'), Willock (Davies 80'), Ashford (Robinson 80'), Salech. Subs Not Used: Turner, Lawlor, Kpakio.
