Dundee United manager Jackie McNamara says victory for his side over Celtic in Sunday's League Cup final at Hampden would be a "massive upset".
It will be the second of four meetings between the sides in two weeks, and McNamara says beating Celtic is an enormous challenge for his players.
"It's always a big ask," said McNamara, who spent 10 years at Parkhead as a player.
"I'm confident we can put on a good show and hopefully cause an upset."
The sides drew 1-1 in an ill-tempered Scottish Cup quarter-final tie at Tannadice on Sunday, and the United boss knows just how tough it will be to overcome their rivals this weekend.
"The gulf in terms of resources, the players that they have, they players that they've taken in the January window, it would be a massive upset for us," McNamara said.
"Celtic are a major force, they've shown that by coming in and taking two of our players in the window.
"My job is to make sure we have other players in there to fill in the gaps and make sure we compete.
"The pleasing thing is our players have worked so hard to get here again in such a short space of time (since losing last season's Scottish Cup final to St Johnstone).
"It would be good for them to lift a trophy."
McNamara, who won the League Cup three times in his playing career, does not think the fall-out from last weekend's Cup tie will have any bearing on Sunday's final.
"I think Sunday was a strange game. A lot of things went on, and in the fall-out from that we're talking about negative stuff rather than the positive stuff.
"Our pitch on Sunday wasn't great for good football, and I think that was a big factor in some of the scenes that went on."
The surface at the national stadium came in for heavy criticism after both League Cup semi-finals, but has since been re-laid, and McNamara hopes it is up to the required standard to allow both sides to provide a decent spectacle.
"I'm hoping the pitch on Sunday, I know it's just been re-laid, but I hope it settles enough, and I can't see it being worse than our pitch last Sunday.
"We won't know how good it is until the players do their warm-up on Sunday."