A penalty shoot-out victory at Cheltenham Town earlier this month set up the Checkatrade Trophy quarter-final at Gigg Lane.
It means a meeting with another Sky Bet League Two side, but with the U’s struggling in League One they are only six places above the
in-form Shakers in the football pyramid.
Brannagan, who scored at Cheltenham, is well aware they are just two wins from the showpiece final, but believes any complacency will see them knocked out. He said: “We can’t take our eyes off our opponents, because they’re a good side. We’ve got to beat them before we do anything else.
“We’ve got to be prepared and take this game as seriously as we can. We’ve got to do everything right.
“You play to win trophies. It’s a big occasion for us – doing well in this competition is very big for us as players.”
Team news – Simon Eastwood’s knee problem ‘not a risk’ for Oxford United’s quarter-final
Brannagan also netted on Saturday, where he put in the miles as United dug deep to claim a morale-boosting league win against Portsmouth.
But with a week’s gap before they are next in action, the former Liverpool trainee knows United can be at full throttle tonight.
He said: “It’s a big game and then we’ve got a few days to chill, so we can put everything into it.
“It was a big win on Saturday, which we needed. That’s given us a booster.
“Hopefully we can take it into Bury and get the win again.”
The weekend’s game also saw United name a stronger squad than they had managed for most of the season.
And knowing they have substitutes who can come on and makes a big difference.
Jamie Hanson said: “On the bench we’ve got game-changers.
“Samir (Carruthers) is back, there’s the likes of (Mark) Sykes, (Ahmed) Kashi, it’s good to look around the changing room and see that.” There will be a reunion on the touchline, where Karl Robinson goes head-to-head with Ryan Lowe, who played for him at MK Dons.
And the U’s boss admitted if the striker was still in his pomp, he would exactly fit the bill in his transfer search.
He said: “I’d love him in this team. He’s such a good goalscorer.
“He’s the type of striker we’re looking for – a fox in the box.
“He’d stretch the game and would play on the last man all the time.”