Leeds have ended the Super League season of Australian tryscoring machine Bevan French and Wigan to reach their 11th grand final.
But the Rhinos may have to do without the services of Australian scrumhalf Aiden Sezer, who had to leave the field for a head injury assessment after he was hit high and late by Wigan's England forward John Bateman.
That was the only sore point for Rohan Smith's men, who produced a remarkable display of grit and determination to condemn 12-man Wigan to their first home defeat of the season in a 20-8 victory.
The Rhinos were under the cosh for virtually the whole of the first half of Friday's semi-final at the DW Stadium but managed to restrict their opponents to a 4-2 interval lead before finding their attacking rhythm in the second half.
Makeshift hooker Jarrod O'Connor scored his first try for the club four minutes into the second half and former St Helens second-rower James Bentley added two more to help Leeds to a stunning win that takes them through to Old Trafford next Saturday.
"I was not at all worried," Smith said of his team's stoical rear-guard efforts in the first half. "It's part of the game.
"I feel there is belief in the group that we could find our way through it.
"Our goal-line defence has been very good for a period of time now, there is a lot of trust and belief. Everyone was calm and relaxed and doing their job.
"Everybody felt good about themselves going in at 4-2."
The only disappointment was Sezer's injury.
"We haven't spoken to the doctor yet," Smith said. "I'm trying to enjoy it for a few minutes. We'll talk about Aidan on the way home."
A first trip to Old Trafford for five years caps a remarkable turn-around in the fortunes of the Rhinos, who were second from bottom of Super League in April after winning just one of their first 10 games.
Smith added: "I came not knowing a lot, but I knew enough to know there was a good group of players and a good group of people.
"I'm really proud and privileged to be part of it. Now the dust is settling, we're starting to think about next week a bit."
"I've no complaints," said Wigan coach Matt Peet. "We understand the rules.
"John had all the best intentions, it was a split-second error. I hope Aidan's okay.
"It would be sad if he got a ban, but I suppose they've got to stick what they've done all season. It would be a shame if misses out on World Cup games."
Wigan's misery was compounded by the loss of French with a foot injury early in the second half and they trailed 20-4 before hooker Sam Powell marked his 250th appearance for them with a late consolation try.
"I'm sad for the group but remain really proud of the group," said Peet. "It's been a special year."