The Owls Under-18s came back after the Christmas break with a closely fought 2-1 defeat away to Nottingham Forest.
Skipper Ayo Obileye pulled Wednesday back into the game, but two first half goals were enough for the home side.
Forest started the brighter and took the lead ten minutes in, as Jake Mulraney crossed from to Josh Thomas, who found the bottom corner.
The home side doubled their lead just ten minutes later when Lawrence Gorman was unmarked in the box and headed home from a close range.
The Owls then hauled themselves back into the game as a free kick from Charlie Dawes dropped nicely for Obileye, who side-footed into the net from a couple of yards.
The hosts almost took the lead early in the second half but the Owls had Elias Moses to thank for a last-ditch tackle.
Wednesday could have drawn level as some good play by Dawes down the left allowed him an effort on goal, which flashed just wide of the far post.
A couple of minutes later, a diagonal ball from Moses fell to Brad Tomlinson, whose shot was deflected off the upright.
With ten minutes to go, Dawes again had a chance to level but his low strike flew wide of the target.
Forest almost made it 3-1 late on but Mayo Balogun cleared off the line before keeper Cameron Dawson made a sharp point blank save.
“We couldn't afford to start the game slow and that made a difference as we conceded two early goals,” said Owls coach Max Wragg.
“I told the players at half time it was unacceptable to start a game like that.
“We came out much better in the second half. We started on the front foot and all the lads got behind each other, and we created quite a few chances that we could have scored from.
“I think we can take the second half performance forward and kick on for the game against Huddersfield next week.”