Cheltenham boss: We'll be 'horrible' against Wigan Athletic
But the Town boss says they won't lie down against the table-toppers, who are looking to extend their unbeaten sequence to 19 matches.
"It’s pretty simple," he said. "We know what they are. Top of the form table, top of the away table. Top of the table with four games in hand.
"I don’t think they’ve lost since October and they’ve not lost away from home since the first game of the season and that was against Sunderland.
"They are the facts and we know all that, so let’s crack on and see what we can do.
"It’s going to be a difficult game, we know that. We have to try and fight and compete, be horrible, be a team scrapping, which we are.
"But we won’t go mad on them. They are a good team with good players and a good manager, clearly, because the league table tells you that.
"We have to focus on what we do. They play a certain way and when we play against this formation, we have to do certain things."
Duff is adamant his side will let Latics know they've been in a game.
"We know Wigan are good, everything tells you they are good," he added. "But we can’t spend all week saying how good they are.
"All we can do is focus on how we can affect how good they are."
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