St Helens prop Jason Cayless has been ruled out of Saturday's Challenge Cup final against Hull after the New Zealand star suffered knee ligament damage.

Cayless sustained the injury in Sunday's 40-22 Super League win at Huddersfield and is certain to miss the Wembley showpiece.

"Jason won't be available until the play-offs," coach Daniel Anderson confirmed.

Nick Fozzard is expected to replace Cayless, while club captain Paul Sculthorpe, Australian back-rower Chris Flannery and former Wigan prop Bryn Hargreaves will make their Wembley debuts after missing Saints' win over Catalans Dragons a year ago.

Anderson will wait until the last minute to decide on the fitness of England's Samoa-born prop Maurie Fa'asavalu, who has a hamstring injury.

"I would be more confident if Maurie had done a training session with us but he still hasn't trained with the team since the semi-finals," he added.

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