Bould is concerned about West Brom - especially their on-loan target man Romelu Lukaku.
He said: "He's a good player and looks like he's going to get better further down the line.
"But West Brom are a good all-round team and it'll be a really tough game.
"I think Steve Clarke has done a magnificent job there. They've been more or less up there in the table for the whole season.
"They've had a little dip but we know it's going to be difficult.
"They've got a good back four, a good goalkeeper and they don't let in an awful amount of goals. We've got a really hard game on our hands.
"We're under no illusions. We know it's going to be a tough game but we're more than capable."