Blackwell said:"The lads need to play at a high tempo because a lot of the teams come to Bramall Lane and shut up shop early, which makes things fustrating for everyone.
"We must make sure we keep our team shape and get the dynamics right. The Lane has always been a fortress and you always leave knowing you have had a tough game."
Blackwell moved on to what the fans job is starting at 3pm.
He said:"I am asking the fans to throw the ball back to the ball boys when it goes into the stands-that way we can use the mult-ball system toinject more pace into the game and that should keep us on the front foot.
"The fans can be the 12th man and in close games their support could be the decisive factor in us winning."