Ross Stewart's goal gave Sunderland a narrow win over Sheffield Wednesday in the first leg of the League One play-off semi-final.
Stewart robbed Sam Hutchinson and kept his cool to score the key goal just before half-time, poking the ball in from a tight angle on the rebound.
Alex Pritchard came closest to adding to the lead, when his curling effort smacked the Wednesday crossbar.
The Owls made the hosts work in the final 20 minutes, but could not score.
Stewart dragged a shot wide with just a minute to go, having almost capitalised on an error by visiting keeper Bailey Peacock-Farrell.