The Seagulls host City at the Amex in their first-ever Premier League game on August 12 after promotion last season.
Manchester City have spent Â£156m so far this summer and when asked about City’s spending, Duffy said: “If they can, why not? It’s a challenge for us.
“If they’re going to compete for the title, that’s what you’ve got to do these days. It’s what you want to play against, if they’re spending Â£100m and we can try to beat them, what a thrill that will be for us.
“It’s what we’ve got to be confident of doing. They’ve got to get to know the players and team, while we have a strong team base together and all know each other’s game.“We’ve got a couple of new additions as well and we’re confident in every game.”
On looking to stay in the top flight, Duffy added: “You’ve got to take it small steps at a time. We know it’s going to be a tough ask but if you’re in the camp, you’ll know everyone is confident and that comes from the manager down.
“He sets good targets. You’ve got to look at teams like Bournemouth and Burnley who have gone up and stayed up. They look like established teams now in the Premier League and if we can go after that for the first season and take small steps, it will be a successful season.”
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