The Owls Under-21s surrendered their unbeaten start to the new season with a 2-0 defeat against Charlton at Hillsborough.
Chances were few at both ends in baking S6 conditions which couldn’t help but have an impact on the intensity of the game.
But the Londoners took the two that mattered through Pat Casey and Toku Ladapo to take the points back south.
A relatively even opening period saw the best opportunity fall the way of the visitors 10 minutes in.
Henry Raylan made headway down the right flank and delivered a perfect low cross to the back stick but Ladapo blazed over with the goal gaping.
Wednesday played more on the front foot after the break and Bailey Cadamarteri threatened on more than one occasion.
A big incident came when Sean Fusire rounded keeper Henry Molyneux and went to ground – the penalty appeals were waved away, though, and the Owls skipper was shown a yellow card for simulation.
Molyneux then saved well from Joey Phuthi, who was impressive throughout before limping out of the action moments later.
And things then got worse for Wednesday as the Addicks promptly opened the scoring with 14 minutes to go.
Ladapo atoned for his earlier miss, sending an unplayable ball right across the danger zone and Casey was on hand to stab home at the far post-
It might have been 2-0 just two minutes after the breakthrough when a looping cross-cum-shot from Ibrahim Fullah came back into play from the crossbar.
But Charlton did double their lead in stoppage time. As the Owls pressed for an equaliser, the back door was open and Ladapo raced through one-on-one to calmly slot past Luke Jackson and secure victory.
Wednesday: Jackson, Phuti (Shipston 70), Flannery (Reed 46), Trialist, Brennan (Adetoro 86), Glover, Cook (Siqueira 46), Wilson, Cadamarteri, Fusire, Wilks (Onukwuli 65)