The young Owls kicked off their 2016/17 campaign with victory, as a second half George Hirst strike earned Wednesday a 1-0 win over Millwall.
In a first half where clear-cut chances were at a premium, both sides took time to forge their way into the game.
The Lions' first real threat came from debutant Paul Rooney's header off a James Brown free kick, but was off target.
Wednesday replied with a chance of their own, as new signing Jordan Thorniley headed just wide from an acute angle.
An alert Dan Wallis prevented the visitors from taking the lead on 22 minutes as he rushed out to close down Alfie Pavey in a one-v-one situation.
Jack Stobbs' 40th minute in-swinging free kick was gathered by Ryan Sandford in the Lions' goal as the teams remained deadlocked at the break.
The second period was an end to end affair, with both teams showing more enterprise.
Wednesday began to turn the screw and almost went ahead when Warren Clarke swivelled inside the Lions' 18-yeard box, but shot straight at Ryan Sandford.
Hirst replaced Devante Rodney on 55 minutes and went on to break the deadlock 15 minutes from time.
The striker latched on to a looping ball over the Lions’ rearguard and struck home in confident fashion.
Millwall had a late chance to nick an equaliser as Kris Twardek's cracking half volley tested Wallis, who dealt with the danger.
The Owls next face Coventry City away from home on 23 August.