Leeds Rhinos booked their place in the Challenge Cup quarter-finals with a convincing victory against St Helens.
Tries from Zak Hardaker, who got two, Joel Moon, Danny McGuire and Jamie Peacock saw off Saints, with Kevin Sinfield landing six goals.
Rhinos winger Ryan Hall picked up man of the match for his efforts.
Saints responded with Adam Swift and Josh Jones tries, both converted by Luke Walsh, but lost prop Kyle Amor to a painful-looking leg injury.
Walsh also struggled throughout with an elbow problem, while Leeds saw hooker Rob Burrow forced off with a knock picked up in a tackle on Joe Greenwood.
"He's broken his collarbone so that's not good," Rhinos coach Brian McDermott said. "I'm being told by the physio that it's 12 weeks but I always try to shave a couple of weeks off that."
McDermott's side - losing finalists in 2011 and 2012 but knocked out by Huddersfield at this stage last season - made sure of their progress with a professional display.
For the visitors, it is now three straight defeats after a tricky Easter period, having won the previous nine league and cup fixtures.
Inside the first minute Saints spilled Kevin Sinfield's early kick-off, one of numerous errors from both sides in a game played at a furious pace.
Leeds took just five minutes to go in front, after a long kick by hooker Burrow was touched by Saints back-rower Josh Jones to force a drop-out.
The kick return saw Kylie Leuluai's drive soften up the Saints line, and a flowing passing move to the right found Hardaker who powered his way through two tackles to score.
Nathan Brown's side soaked up the pressure and turned defence into attack when Jon Wilkin gathered Burrow's kick on the full in goal to earn a 20 tap.
From there Saints poured forward, a fine Sia Soliola pass set Mark Percival through a gap and he held his pass perfectly, freeing Swift on the left to score despite the attentions of Kallum Watkins.
Danny McGuire had a try chalked off when he swooped on Luke Walsh's spill with the tackle already called, but the Rhinos did add a second try to go back in front before the half-time hooter.
Hardaker again finished off the move, which came from a scrum for a ball-spill by Tommy Makinson and a typically bulldozing run and offload from Ryan Hall.
Sinfield added to the Rhinos' tally after the break from the tee to punish St Helens' indiscipline and soon after Joel Moon touched down on the left after Sinfield and Ablett had combined to stretch the visitors' defence.
Jones found space to coast through the Leeds defence from Lomax's short ball to reduce the deficit for Saints, but not even a Luke Walsh 40/20 kick could inspire a crucial third try as Rhinos committed well in defence.
McGuire then made sure of the win when he popped to collect an inside pass from Watkins to strike for the Rhinos' fourth try and Peacock made sure he had the last word with a typically powerful finish from close in with minutes to play.
Leeds Rhinos coach Brian McDermott:
"I'm not so excited about the performance, certainly not with the ball. Our desire in defence got us that game. The second half was very scrappy but I'd that down to nerves.
"There was a huge amount resting on today. There had to be a loser of two teams who have a massive expectation. We certainly played nervous and I reckon Saints would admit to that as well.
"I'm absolutely ecstatic to be in the next round but will have to be a lot better to progress further in this competition."
St Helens coach Nathan Brown:
"Once again we started the first set with a dropped ball and we were defending our try-line for a fair period.
"Defensively I thought we handled them pretty well until that try just before half-time which was quite crucial.
"We let ourselves down a little bit with a flow of our attack. Our game management was just so-so."
Leeds Rhinos: Hardaker; Briscoe, Watkins, Moon, Hall; Sinfield, McGuire; Leuluai, Burrow, Peacock, Ablett, Achurch, Delaney
Substitutes: Kirke, Clarkson, Sutcliffe, Singleton.
St Helens: Lomax; Makinson, Turner, Percival, Swift; Wilkin, Walsh; Amor, Roby, Walmsley, McCarthy-Scarsbrook, Soliola, Jones
Substitutes: Richards, Wellens, Masoe, Greenwood
Referee: Richard Silverwood