The American is in his first full season in charge at Elland Road, but needed no reminding of Cardiff's famous cup upset in 2002 when the then third-tier side won 2-1 against Leeds, who at the time were top of the old Premiership.
Marsch said: "I know the history of us losing 21 years ago at Cardiff and we expect they will be very spirited for this match.
"We know 6,000 (Leeds) fans are going down, so we want to put the best team we can on the pitch."
Leeds have a wretched FA Cup record. Winners for the only time in 1972, they have gone beyond the fourth round only three times since that humbling defeat to Cardiff.
The Whites have also lost 14 times to the Welsh club in 22 meetings since losing that day in 2002, winning on just three occasions, while in each of the last six years Leeds have fallen at the first hurdle in the FA Cup.
Marsch said: "This is why even when we got the draw we spoke about it and we knew it was going to be a difficult draw for us.
"It's a long way by English standards, not American. But it's about having a clear mindset and expecting the best from them and being ready for that.
"It will be a cup fight and our ability to play the way we want to play, but to understand exactly the mindset of the opponent and for us to be ready for a real match, absolutely in every way.
"I've been on different ends of what a cup match can be, David and Goliath, as both player and manager."
Leeds' hierarchy also feel it is time to set about putting their woeful FA Cup record right.
"(Chief executive) Angus (Kinnear) subtly spoke to me last week and said maybe we should focus on having a good FA Cup run," Marsch added. "I said 'message received'."
Marsch confirmed new signing and former Salzburg skipper Max Wober could make his Leeds debut after joining for a reported fee in the region of £10million on Tuesday.
Patrick Bamford returned to full training this week after undergoing groin surgery during the World Cup break, but Marsch was not sure if the striker would be ready for Sunday.
Adam Forshaw (hip) and Luis Sinisterra (foot) remain unavailable, while Marsch revealed Stuart Dallas had had a third operation due to an infection as he recovers from a fractured femur, sustained in May last year.