Boss Brian Laws warned his Sheffield Wednesday side to start games better after they suffered a 1-0 home derby defeat at the hands of Barnsley.
The Owls went into the game on the back of a victory over city rivals United, but were unable to replicate their fine performance at Bramall Lane.
Laws told the Sheffield Star: "The game was there for us to take it to them, but that's the second time we've been poor in the first half.
"We have to do better and we have to start better than that. The first half has been the catalyst for us losing the game.
"We can't wait for the second half, we have to do it in the first.
"I'll be looking for a response and we know we're going to be in for tough one against Crystal Palace on Saturday."