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80 mins: FULL-TIME Huddersfield 12-42 St Helens
Saints are in possession and they are content to wind the clock down. The hooter goes and St Helens celebrate their first trophy under coach Daniel Anderson. Sean Long is awarded the Lance Todd trophy and is the first player to win the Challenge Cup man of the match three times.
79 mins: Paul tries to create a try as Giants aim to finish with a flourish, however, his kick is well covered by the Saints defence.
76 mins: A smothering tackle on his own line from Cayless prevents Huddersfield scoring.
73 mins: TRY Huddersfield 12-42 St Helens
Saints are looking dangerous again and Long's grubber into the in-goal area causes chaos in the Giants defence. Prop Jason Cayless, looking as battered and bruised as Wilkin, barges his way through to touch down and after consultation with the video ref - the try is given. Lyon adds another two points.
70 mins: TRY Huddersfield 12-36 St Helens
The Giants are battling bravely despite their predicament. Drew decides to kick early and places a deft kick over the top to get Robbie Paul on the scoresheet. De Vere kicks the goal.
67 mins: TRY Huddersfield 6-36 St Helens
Cunningham shows electric pace from a play-the-ball to leave the Giants defence trailing. He gives the ball to Wilkin, who has the simple task of claiming his second try. Lyon kicks his sixth goal from in front of the posts.
63 mins: Huddersfield make a rare foray forward but the ball is lost by Steve Snitch. The Giants look like a beaten team now and Saints have had 60% of the second-half possession.
57 mins: TRY Huddersfield 6-30 St Helens
Long's dummy puts him through and his sublime kick to the corner is a gift for Lyon, who dives, catches and scores in one movement. The Saints centre, who has now scored in every round of this year's Challenge Cup, dusts himself down to fire the conversion over from the touchline.
"Huddersfield have to change their game plan now. The Saints defence is controlling them and they are not getting the yards they did in the first half."
51 mins: TRY Huddersfield 6-24 St Helens
It is surely all over for Huddersfield now. Roby's grubber kick from 10m out is perfectly weighted and Fa'asavalu touches down. Lyon adds the extras.
48 mins: Huddersfield try to get out from under their posts after a Gardner attack breaks down. Giants winger Stuart Donlan is flattened by a high tackle from Wilkin, who is now covered in blood. Despite the boos from the crowd, Wilkin is not dismissed but is placed on report.
44 mins: TRY Huddersfield 6-18 St Helens
Maurie Fa'asavalu smashes his way through the Giants defence. He offloads to James Roby who is brought down by Chris Nero but there are just too many numbers and Jon Wilkin, who has a strapped up nose after an earlier collision, dives over to put his side in control. Lyon collects his third conversion.
42 mins: Saints threaten early on. Pryce produces a superb offload to set up Long, who tries the same but the ball goes forward.
41 mins: St Helens get the second half started.
1543: Huddersfield are the first ones out while St Helens take their time in taking the field.
"Now St Helens are in a bit of rhythm. They have withstood the best Huddersfield have thrown at them and if they get enough possession in the second half, one on one they could be too strong and skilful. They could run away with it in the second half."
"For a quarter of the half Huddersfield were on top with their kicking game and their kick chase but St Helens were patient and brought the ball back a lot further on each of the kicks.
"Now it is about belief, Huddersfield can still score points. To win now they will have to be a little different than they were in the first half."
40 mins: HALF-TIME Huddersfield 6-12 St Helens
With Twickenham bathed in late August sunshine, the hooter goes and the teams go off for half-time.
36 mins: TRY Huddersfield 6-12 St Helens
Centre Lyon jinks and twists to create a break when there does not seem a lot on. Gardner is in support and he waits to give a perfectly timed inside ball to Long who has enough gas to score. Lyon kicks the goal.
34 mins: Pryce breaks through the defence to set up an ominous Saints attack. It looks promising but Long drops the ball just five metres out. Possession is now 57% in St Helens' favour.
29 mins: O'Reilly is the Huddersfield hero when he produces a wonderful covering tackle on Ade Gardner who seems odds on to score after a stunning break down the wing.
28 mins: A precision kick into the in-goal area forces Wellens to play the ball and run it back into play. He has to take a little breather though as he is on the wrong end of another big hit.
27 mins: Cunningham is fortunate to escape punishment after what seems a high shot on Giants full-back Paul O'Reilly.
23 mins: Painful moments for Saints loose forward Jason Hooper after he is flattened by a forceful double hit. It does not help that one of the tacklers is none other than Eorl Crabtree - nephew of wrestling legend Big Daddy. Uncle would have been proud.
21 mins: TRY Huddersfield 6-6 St Helens
St Helens attack again, helped by some go-forward from their pack. Paul Sculthorpe's grubber kick bounces off Drew's leg right into the arms of Willie Talau who has no problems in scoring. Jamie Lyon adds the conversion.
"When the break is there from Saints, it is all a bit flat. There is no support." BBC Sport summariser Jonathan Davies.
18 mins: St Helens scrum-half Sean Long kicks over the Huddersfield defence as his side press forward. However, as Saints try to claim the ball just inches from the Giants line, it is knocked on.
16 mins: Huddersfield's impressive start is signalled by a television graphic which shows that they have had 55% of possession and territory.
14 mins: Huddersfield loose forward Stephen Wild rips the ball off Francis Meli in the tackle but the Giants do not get possession as referee Richard Silverwood, following discussion with his touch judge, rules that the tackle had been completed.
13 mins: The game is settling down after that electric opening. St Helens are just content at the moment to get back into the match by completing their sets of six.
6 mins: TRY Huddersfield 6-0 St Helens
Acting dummy-half Brad Drew is given acres of space at a play-the-ball on the 40m line. He storms through the Saints line and the ball makes its way to wing Martin Aspinwall who dives over in the corner for the opening try. Michael De Vere adds the goal. What a start.
3 mins: Saints just can't get out of their own half. Giants skipper Chris Thorman dabs a cheeky grubber kick into the in-goal area but Paul Wellens clears up well.
2 mins: The Giants are up for this. Kieron Cunningham tries to get out from under his posts but he is set upon by a swarm of Huddersfield shirts and is dumped in goal.
1 min: Huddersfield start the game and immediately there is a mistake by Saints. The ball is not collected by Leon Pryce and it bounces off his leg into Giants' hands, who immediately threaten the St Helens line.
1443: League legend Martin Offiah is introduced to both teams and as the firework smoke starts to clear, the national anthem is belted out. Everything is ready and kick-off is now upon us.
1439: The teams are led out and are met by a firework display, loud music and a rapturous reception from the crowd.
"I think Saints will win but by a close margin. But if it is close at half-time then I'll go for Huddersfield - so that's sitting on the fence for you."
"Saints have a great side and you would be nuts not to think they will win but I'm going to be like Brian and see where we are at half-time."
1436: As the two teams appear in the Twickenham tunnel, the strains of Challenge Cup final anthem "Abide With Me" ring around the stadium.
1431: "Huddersfield have to start well. If they are close after 20 minutes then they have a real chance."
Wigan and Great Britain coach Brian Noble
1429: The crowd, boasting shirts and flags from all around Super League, are enjoying the pre-match entertainment - which at the moment is coming from the London Community Gospel Choir.
1426:"Preparation is vital, it is all about what you do during the week. You want to build up and not play the game before you get there."
Former St Helens coach Ian Millward
1423: The green seats of Twickenham are slowly filling up as kick-off approaches. It is dry in south west London at the moment but a little cloudy - in short, perfect rugby league weather.
Huddersfield are looking to score a massive upset against Super League leaders St Helens in the Challenge Cup final at Twickenham.
The Giants, in their first Cup final for 44 years, are without prop Keith Mason, but skipper Chris Thorman has been passed fit after recovering from a hamstring injury.
St Helens, who last won the competition in 2004, are looking to get their hands on the trophy for the fifth time in 11 years.
Daniel Anderson has a full-strength squad to choose from and has been able to leave out such big names as Nick Fozzard and Vinnie Anderson.
Scrum-half Sean Long, who was part of the Saints team that beat Bradford in the last final at Twickenham in 2001, is chasing a record-breaking third Lance Toddy Trophy award, given to the man of the match.
Legendary BBC commentator Ray French, a winner of the Challenge Cup with St Helens, is commentating on his 25th successive final.
Live coverage on BBC One, Radio Five Live and this website
Huddersfield: Reilly, Aspinwall, Nero, De Vere, Donlan, Thorman,
Paul, Jackson, Drew, Gannon, Crabtree, Raleigh, Wild.
Replacements: Snitch, Jones, Smith, McDonald.
St Helens: Wellens, Gardner, Lyon, Talau, Meli, Pryce, Long,
P Anderson, Cunningham, Cayless, Wilkin, Sculthorpe, Hooper.
Replacements: Gilmour, Roby, Graham, Fa'asavalu.
Referee: Richard Silverwood (Dewsbury).