It will be one of the most important derby matches in years with relegation-threatened Wednesday desperate for .
Irvine told The Star: "The usual pride and bragging rights are at stake, but the biggest thing is the points.
"They have some good players and they're a powerful team.
"They work extremely hard, they have threats up front and it's a very tough game for us."
Meanwhile, the Blades head into this weekend's clash short on derby day experience.
But boss Kevin Blackwell insists his side will be under no illusions about what will await them at Hillsborough.
He told The Star: "I'll be showing them the DVDs of recent meetings between us, I'll be showing them the games.
"I'll be telling them that families will be tormented depending upon the result of this match.
"If they are in any doubt then we'll get them to understand.
"They are all professionals who've been involved in big games in the past. These games are special though, there's no doubt about that.