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Result: Catalans Dragons 20-36 St Helens
Result: Huddersfield Giants 24-16 Hull FC
Holders St Helens & Huddersfield join Hull KR in the semi-finals
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Morgan Knowles, goal Tommy Makinson
Joe Batchelor almost gets his way through 20 metres out but Mike McMeeken thwarts his efforts but St Helens continue pushing.
Catalans try to stop them, but Morgan Knowles crashes over to stretch out Saints' lead.
Tommy Makinson swings a tremendous conversion to add the two.
Catalans 10-20 St Helens
Every time St Helens put together a string of passes, it just stuns the home crowd into silence.
Louie McCarthy-Scarsbrook does well to pirouette his way through the Catalans back line, leading to a good spell for the visitors before the Dragons regain the ball on the turnover.
Catalans 10-20 St Helens
We're back under way at Stade Gilbert Brutus.
About another 30 seconds until Curtis Sironen is back on the field.
HT: Catalans 10-20 St Helens
Sylvain Houles
Toulouse head coach on BBC One
Jack Welsby's creating and he's always at the end of the play.
It's huge for St Helens because he's a unique player, he has the ability to do everything.
HT: Catalans 10-20 St Helens
Jon Wilkin
Former England international on BBC One
We spoke about Jack Welsby and how important he is. His combination with Lewis Dodd is incredible.
Catalans 10-20 St Helens
Breathtaking rugby league.
An entertaining display between these two Super League giants.
Catalans have clawed their way to within 10 points after St Helens's earlier dominance.
This ain't over.
Catalans 10-20 St Helens
Fouad Yaha should be clean through!
Arthur Mourgue finds the Catalans try-scorer with a corker of a pass and he should be running in with ease at the corner once more.
But he spills the ball. What a waste.
Catalans 10-20 St Helens
Meanwhile, while we were distracted by that Curtis Sironen yellow card, Catalans full-back Sam Tomkins limped off.
He's now holding ice to his upper calf on the sidelines, but he may be able to return in this game later on, according to BBC Sport's Damian Johnson.
Gil Dudson, goal Arthur Mourgue
That didn't take long!
Gil Dudson goes over under the sticks no sooner does Curtis Sironen get sent to the bin.
An easy try for the hosts and just what they need after being on the receiving end of a wave of St Helens dominance for most of the first half.
Arthur Mourgue brings the hosts within 10 points as he adds the extras.
Catalans 4-20 St Helens
There's some afters following a Curtis Sironen challenge from behind on Ben Garcia, who was in the process of getting up off the ground.
Sironen sees yellow, which is probably deserved.
Can Catalans take advantage of their player advantage as St Helens close out the half with 12 players?
Catalans 4-20 St Helens
Catalans could do with half-time right now, to be honest. They look stunned.
The red and yellow ticker tape from the pre-match festivities lining the pitch looks pretty ironic now, given how poorly the hosts have performed in the past 10 minutes.
Catalans 4-20 St Helens
Brian Noble
Ex-Great Britain coach on BBC One
St Helens are playing too quick for this Dragons team.
Mark Percival, goal Tommy Makinson
Catalans are all over the place. St Helens go in again through Mark Percival!
Some try this, as well. Percival bolsters his way over and the Dragons just looked short of answers.
Tommy Makinson nails yet another kick to add the two.
Catalans 4-14 St Helens
Brian Noble
Ex-Great Britain coach on BBC One
The last two sets we've seen, you cannot clock off against this St Helens side.
You have to be with them set for set, play for play. The minute you take one foot off the gas, they will burn you.
Lewis Dodd, goal Tommy Makinson
Wow. St Helens are coasting, here. Two quickfire tries!
A sumptuous set of passes eventually sees Jack Welsby involved in yet another try as he works onto a late Curtis Soronen pass, he gallops forward and tees up Lewis Dodd to cross over.
Tommy Makinson adds the two.
Jack Welsby, goal Tommy Makinson
Jack Welsby picks up the ball deep in his own half and the St Helens full-back runs pretty much unopposed, winning back a good 20 metres.
He exchanged passes with Will Hopoate and goes over, stunning the Catalans back line who were completely caught out by Welsby's good passing.
Tommy Makinson makes it two from two with the boot as he adds the extras.
Catalans 4-2 St Helens
Brian Noble
Ex-Great Britain coach on BBC One
That's brilliant from the Dragons. First you get the juggernauts and the diesels laying the platform and then the speedcars came in.
All Yaha had to do was put the ball down in essence.
Fouad Yaha
Great stuff from Catalans and you can't say that hasn't been coming.
Josh Drinkwater's movement is what does this as the hosts move the ball quickly, swarming the St Helens defence before Fouad Yaha runs in at the corner.
Sam Tomkins sends his conversion wide. Two point game.
Catalans 0-2 St Helens
Brian Noble
Ex-Great Britain coach on BBC One
This is already good, isn't it?
It's bish bash and painful for both teams.
Catalans 0-2 St Helens
There's a break in play as Gil Dudson walks off to receive treatment.
Catalans had been playing essentially with 12 players for a moment before the pause.
He's off for a head injury assessment.