Ben Osborn's stoppage-time goal gave Stockport County victory over Stevenage in the League One play-off semi-final first leg.
Osborn poked the ball home with the final kick of the game after a lapse of concentration by Boro defender Carl Piergianni.
Piergianni had earlier missed with two headers, squandering chances to put the hosts ahead.
Stockport had been frustrated in front of goal but are now favourites to progress ahead of Wednesday's return leg.
Kyle Wootton, Stockport's top scorer - but playing as a makeshift centre-back - almost opened the scoring from an Ollie Norwood corner in the first minute but could not guide his header on target.
Stockport's Adama Sidibeh wasted the first real opening of the game. After springing forward on the counter-attack, he mistimed his pass to Louie Barry, who would have been in on goal had he connected.
At the other end, Jordan Roberts headed the first effort on target, but he could not generate enough power and it was easily collected by Corey Addai in the County goal.
Roberts again forced Addai into a save from the edge of the area a minute before half-time. Following the resulting corner, Roberts turned provider for Piergianni, who was unable to guide his free header goalwards.
Stevenage's Dan Kemp had a sight of goal four minutes after the restart, turning well into space before driving forward. His shot was tame, though, and drifted wide.
Sidibeh almost capitalised on a poor clearance by Piergianni on the hour mark, but he was stretching for it and hooked his first-time shot wide.
Kemp and Roberts then combined, and the former raced away but went down under a challenge from Tayo Edun, who made up for his initial error in giving the ball away. No penalty was given.
Piergianni again missed the target with a free header after 76 minutes, nodding over from Phoenix Patterson's free-kick.
With the game petering towards stalemate, Benony Andresson robbed Piergianni before slipping at the vital moment, but Osborn was on hand to finish.