The Owls’ Under-18s fell victim to some ruthless finishing by Birmingham and suffered a 4-1 away defeat.
The league clash in the Midlands was a close encounter in terms of possession but the hosts had a cutting edge that sliced through the visiting defence.
The upshot was a scoreline that hardly reflected the balance of play but a harsh lesson for the Wednesday youngsters.
Coach Steven Haslam said: “It was a fairly even game but we switched off at times and were punished by a ruthless Birmingham side.
“Jake Nicholson was a bright spark when he came on and scored a cracking goal but overall we didn’t reach the standards we expect.
“I’ll be looking for the boys to respond now in the two games we have this week.”
The Under-18s have two home derby fixtures on the horizon, both of which take place at Middlewood Road.
First up is Barnsley this Tuesday (12.30pm) then Sheffield United on Saturday (11.00am).
Entrance is free and all supporters are welcome to attend.