The Owls Development Squad posted their first win of the campaign on Monday evening at Ashton Gate.
Goals from James Demetriou and Brad Beatson secured victory over Bristol City in the 2-1 win.
The Robins hit back late in the game to halve the deficit through a Will De Havilland own goal but Wednesday held on to their one-goal lead.
Following a goalless first period, the Owls went ahead shortly after the restart through trialist Demetriou who nodded home from close range.
That lead was doubled moments later when Beatson volleyed home in impressive fashion past Robins goalkeeper Max O’Leary.
Cameron Dawson was in fine form throughout the evening and it took a moment of fortune for the hosts to beat the Owls' academy product.
Tom Fry’s cross caused confusion in the danger zone and the ball deflected over the line off De Havilland.
Wednesday endured one final scare as Robins striker Shawn McCoulsky raced clear in injury time but fired against the underside of the crossbar.