Brentford memorably thrashed 4-0 in August and Thomas Frank expects the Red Devils to be looking for revenge when the clubs meet again on Wednesday night.
On an unforgettable afternoon for the Bees at the start of the season they stuck four past their visitors within the first 35 minutes of the game and then strolled to a huge win.
It was part of a nightmare start to the season for , shortly after he took over as Manchester United manager, but things have improved significantly since then.
United have won the Carabao Cup and are well-placed to claim a spot, although they have wobbled of late, with defeats to Newcastle and Liverpool and a draw with Southampton.
However, Frank does not expect to face the same kind of limp challenge Brentford faced in August and predicts an energetic and aggressive Red Devils performance.
‘I know it will be unbelievably difficult,’ Frank said of the clash with United on Wednesday.
‘They will come flying out and fighting for every single ball. They’ll be showing unbelievable determination, they’ll be on top of everything, and their skillset is absolutely frightening when you look at the players they have in their squad.
‘It will be difficult but, of course, we believe in ourselves that we can do something.
‘That was a very, very good win in the history of Brentford.
‘I don’t want to run away from that – we are very proud of that. But we know it will be a completely different game on Wednesday night.
‘It’s a big credit to Manchester United’s history and what they’ve achieved when you look at how much that win meant to us.
‘That’s what comes when a club has done fantastically over the last 30 years, with that golden era and when they won everything under (Alex) Ferguson.
‘For us to beat them is a big thing. But that’s history, we can’t use that for anything on Wednesday night. That was a completely different game.’
Brentford are enjoying an impressive season themselves, sitting seventh in the table and with a chance of an unlikely European finish.
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