Mark Warburton is expecting a battle against Millwall as the Lions are fighting to survive in the Championship.
The south Londoners are deep in the relegation mire, six points from safety, and Brentford will be looking to maintain their push for promotion.
Millwall sacked manager Ian Holloway, replacing him with club legend Neil Harris and Warburton believes his genuine passion will rub off on his players.
He said: “It's a tough division with big clubs down there. The players fought for Ian Holloway but the random nature of the game.
“Neil Harris' reputation is fantastic at the club. He's got a genuine passion for the club. He's already spoken about the Millwall way.
“They will be hunting in a pack to get the ball back and play with a real determination.”
Millwall's Achilles heel has been defending set-pieces, while Brentford have struggled to score from them.
Warburton, though, deemed it to be the randomness of the game, believing they have come close on several occasions.
He said: “Harlee Dean had a great header that forced an outstanding save (from a corner) the other night.
“You'll always look at each area but they've been top six. Any concerns are cooled then we're doing okay.
“I'm not frustrated. We've had blocks off the line and free kicks. The amount of set piece work we do and we've been very unfortunate.
“Time and time again the random nature of that hasn't fallen our way but we've got goals from all over the park with strikes from Andre Gray, Jonathan Douglas and Alex Pritchard. I'm delighted with the variety of goal resources.”
