Graham Potter knows Swansea City will face one of the best sides in the world on Saturday, but has urged his players to believe they can cause an FA Cup upset against Manchester City.
The Swans play the fifth FA Cup quarter-final in their history when they hosts Pep Guardiola's Citizens at the Liberty Stadium (5.20pm), and they will inevitably start as major underdogs.
Manchester City are still in the hunt for a quadruple, they have already won the EFL Cup, top the Premier League and are in the last eight of the Champions League following their midweek thumping of Bundesliga side Schalke.
Victory against the Swans will send them into the last four of the cup, and Swans boss Potter - who attended the Schalke game on Tuesday - is fully aware of the awesome challenge facing his young side.
But he insists that anything can happen in a one-off knock-out fixture, as long as his players go out on the pitch with a genuine belief they can topple the Premier League champions.
"They are a fantastic football team," said Potter.
"Clearly they are the best team in the United Kingdom, they are one of the best teams in the world. Essentially, that is what we are facing.
"So we face a huge challenge, a brilliant challenge for the players because you get to test yourself against the best, and we have to try.
"That's how it is, it is a one-off game. Over a two-legged tie or more than that you've got no chance pretty much, because the quality is so high.
"But in a one-off match anything can happen and we will try to manufacture something from that.
"We have a chance to get to the semi-finals of the FA Cup, which is exciting.
"You have to go into the game thinking you can win, otherwise there is no point.
"You respect how good the opposition are and the odds are stacked against us. But it's a one-off game, you have to believe you can win."