A first half penalty from Alan Gow condemned the Owls to defeat at Hillsborough against Notts County.
Wednesday enjoyed the lion's share of possession throughout the contest but the Nottingham outfit carved the best chances and Nicky Weaver came to the rescue on numerous occasions for the hosts.
By contrast, County keeper Stuart Nelson was untroubled and his side emerged with all three points.
The Owls bossed the early exchanges without making any real inroads on goal but the signs were looking good for Gary Megson's men.
Wednesday were comfortable all over the park and particularly in the midfield area, where County were second best.
And although chances were at a premium, the Owls were clear favourites to draw first blood.
But as so often is the case in football, the sucker punch came and Wednesday found themselves one down on 26 minutes against the run of play.
Gow and Mark Beevers came together down the left side of the penalty area and the forward went to ground.
The referee pointed to the spot and Gow got up to despatch low past Weaver from 12 yards.
The visitors - until that point subdued - took a visible lift and Kevin McDonald tested Weaver with a daisycutter that the Owls' keeper parried clear.
And Weaver was the difference between the Owls staying in the game and County taking a 2-0 lead into the break.
With three minutes to go before half time, Njogu Demba-Nyren had a golden opportunity from close range but his header was expertly diverted by Weaver.
The rebound fell kindly to Demba-Nyren, whose stabbed effort rolled the wrong side of the post and Wednesday went down the tunnel down but not out.
Megson introduced Jermaine Johnson and Daniel Jones for the second half and the Owls began on the front foot.
Clinton Morrison was a whisker away from getting something on Tommy Spurr's free kick before the same player missed his connection from another Spurr feed.
But Wednesday were then fired two warning shots inside a minute. First Demba-Nyren brought another fine save from Weaver, then Ivan Sproule flicked wide after breaking into space in the area.
The Owls pressed on, though, and Michael Morrison went close following a Gary Teale corner.
Neal Bishop flashed an arcing shot wide at the other end as the Owls pushed forward in numbers and skipper Tommy Miller went close with a thundering drive from distance.
Jones drilled wide in the closing stages after Clinton Morrison shot over the bar and by then it was becoming clear it was not going to be the Owls' day.
And so it proved as Wednesday failed to find a way through a solid rearguard, leaving County to take the short hop back to the Midlands triumphant.
Owls: Weaver, M Morrison, R Johnson, Beevers, Spurr, Sedgwick (Jones 46), Osbourne (O'Connor 68), Miller, Teale, C Morrison, Mellor (J Johnson 46)
Unused substitutes: O'Donnell, Coke, Potter, Heffernan
Notts County: Nelson, Darby, Edwards, Lee, Bishop, McDonald (Spicer 86), Gow (Brandy 86), Sproule (Chilvers 90), Clifford, Harley, Demba-Nyren
Unused substitutes: Burch, Sodje, Williamson, Hollis