The Owls’ Under-18s went down 1-0 to ten-man Charlton at Middlewood Road last Saturday.
The Londoners scored the only goal of a game with few chances in the second half after earlier having Sam Nwosu sent off for hauling George Hirst back when the striker was through on goal.
The decisive strike came on 65 minutes when Alex Willis’ looped header from a set piece from the right flank sailed into the net.
For Wednesday’s part, the Charlton keeper was tested only once late in the second period when substitute Layton Swaine aimed a snapshot on goal.
Wednesday: Wallis, Hughes, West, Kirby, Lee, Cook, Lonchar, Waldock (Swaine 80), Hirst, Hunt, Preston