Leroy Cudjoe intercepted Leeds on their usual route to Wembley with two tries that took Huddersfield into the quarter-finals of the Challenge Cup.
The England centre twice picked the Rhinos' pockets for long-range interceptions, but that was only the cutting edge of a steely Giants' performance. They defended magnificently in the second half – especially after Joe Wardle's sending-off on the hour – to deny Leeds, who have been beaten finalists in the last three seasons. "We enjoy fighting for our lives," said Huddersfield's Eorl Crabtree, who put in a massive shift at prop.
It was a compelling contest from start to finish. Two goals from Danny Brough and Shaun Lunt's close-range try gave the Giants an early eight-point lead. It would have been more but for Zak Hardaker's try-saving ankle grab on Crabtree – after which Leeds went straight to the other end and scored through Kallum Watkins.
If that looked like a turning point, Huddersfield refused to be knocked off course, scoring almost immediately through Wardle, after good work down the right by the man of the match, Cudjoe.
The centre then capitalised on his first interception, deep in his own territory from Mitch Achurch. That was the easy part; beating Hardaker and Carl Hall on the way to the try-line was the hard bit.
Brough's long kicking game then kept Leeds pinned back for much of the first half. After the break, Brough edged his side further ahead with a penalty but, when Wardle was dismissed for raining several blows on the head of Carl Ablett, there was still plenty of time for the Super League champions to exploit their advantage.
It looked ominous for the Giants when the impressive Watkins went over for his second try, but then a couple of other chances went astray for the visitors before Cudjoe picked off Danny McGuire's pass to romp away delightedly for the clinching try.
It had been a classic try, worthy of Wembley itself, but there was no disputing Huddersfield's right to take a step in that direction. "To beat Leeds with 12 men shows the character we've got," said Brough, who kicked the final goal.
"Huddersfield played better than we did," said Brian McDermott, the Leeds coach. "We made some uncharacteristic errors, it was a combination of things. I'm very disappointed with the result, but I've no real complaints."
For the Rhinos, there was also the unusual experience of Kevin Sinfield, the captain, failing to kick a goal. At least he and his team will avoid their usual frustration at Wembley this August.
Huddersfield Grix; McGillvary, Cudjoe, Wardle, Murphy; Brough, Robinson; Crabtree, Lunt, Kopczak, Chan, Ferres, Ferguson. Substitutes used Patrick, Faiumu, Ta'ai, Cording.
Leeds Hardaker; Watkins, Ablett, Moon, Hall; Sinfield, McGuire; Leuluai, Burrow, Peacock, Delaney, Jones- Buchanan, Achurch. Substitutes used Kirke, McShane, Clarkson, Bailey.
Referee P Bentham.