Owls star Fernando Forestieri was named as the Sky Bet Football League Man of the Match after the 2-1 win over Rotherham.
Following a goalless first half, Wednesday went ahead in less than 30 seconds after the restart through Lucas Joao.
Forestieri did superbly well in the first instance to win possession and test Lee Camp, and as the Millers goalkeeper made the save, there was little he could do to keep out Joao’s close range conversion.
The Owls then hit a quickfire second goal through Forestieri, who pounced on another rebound from Daniel Pudil’s header to stun the hosts.
Head coach Carlos Carvalhal said: “Fernando did fantastic in the second half, as did all the players.
“I still think Fernando is working at 60-70%, he still has more than 30% to get better and he will do.
“When he joined us he was not 100% but he is getting there.”