Swansea boss Graham Potter maintains his players must believe they can upset the odds and pull off a shock FA Cup victory over Manchester City and their "best coach in the world".
The Welsh club have struggled for consistency following relegation from the Premier League, and are currently mid-table in the Sky Bet Championship.
Nevertheless, Potter's side are within 90 minutes of reaching the FA Cup semi-finals at Wembley – provided they can get the better of a City side out to keep on course for a potential clean sweep of all four trophies.
Potter feels his players must go into Saturday's 5:20pm kick-off at the Liberty Stadium with a positive mindset – no matter the quality of opposition on the pitch and in the dugout.
"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," said Potter, who watched City take apart Schalke 7-0 on Tuesday night to book their place in the last eight of the Champions League.
"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.
"There is a gulf in quality, with respect to the Championship, it is not just one level, it is a few levels.
"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."
Former Barcelona and Bayern Munich coach Pep Guardiola has made a seamless transition into the English game.
Earlier this season the Spaniard also guided his side to Carabao Cup success when beating Chelsea on penalties at Wembley to add another trophy to the collection.
"Personally, when you look at what he's done, I can't argue against him being the best coach in the world," Potter said at a Swansea press conference reported by the club on Friday.
"The process they have been on, from questioning whether his methods can work in the British game to breaking the Premier League points record (last season), it is amazing.
"When you look at the three teams he (Guardiola) has managed, he has had a huge influence on them all. He adapts to the quality of his players."