Owls manager Jos Luhukay said the game was lost in the first 15 minutes following Wednesday’s 4-2 defeat to QPR at Loftus Road.
Three goals in 15 minutes for Rangers from Paul Smyth, Jake Bidwell and Idrissa Sylla set the pace in the capital before a penalty from the latter all but sealed the result.
There was hope for a comeback when Fernando Forestieri and Atdhe Nuhiu grabbed second half goals, but it was too little too late for the Owls.
Luhukay said: “We lost the game in the first 15 minutes by conceding three goals.
“This makes it very hard for the team to come back into the game.
“The players worked very hard, they did not stop or give up, but unfortunately there was not much we could do after being 3-0 down.
“We have to defend the final 30 metres much better and that is what we must do moving into the next game and beyond.
“After the first 15 minutes we got better and better and played our way back into the game but we conceded a penalty at that point.
“It was very hard to get anything from this match, but we grew stronger and got two goals, and near the end we almost got another.
“But this was not our night, and like I say, the game was lost in the first 15 minutes.”