The scrum-half has been sidelined since suffering nerve damage in his neck playing against Bradford Bulls in early April but was given the go-ahead to resume training last month.

Although Horne has made a full recovery, he has lost considerable condition during his extended lay-off and remains more than a stone underweight.

Horne, 26, is undergoing intensive rehabilitation this week in an effort to get him ready to play and will work alongside Adam Dykes, the Australian half-back whose outstanding work in the semi-final victory over Wakefield played an important role in Hull reaching Wembley for the first time since 1985.

Dykes's fitness for the final remains in considerable doubt because of long-running shoulder and knee injuries.

Both players attended yesterday's pre-Cup final media day and photocall at the KC Stadium but were whisked away as soon as the official photographs were taken and were not available for interview.

"We will take some guidance from the player himself on whether he's mentally ready, but I think he's been in the game long enough to know he would only go out there if he was confident he could be an effective player," said Hull coach Richard Agar. "I have a lot of faith in Richard to make the right decision."

Selecting either player would be a huge gamble but one Agar cannot avoid in the absence of any other recognised half-backs.

Danny Washbrook is expected to retain the No 6 role but the back row forward needs a creative presence alongside him if Hull are to wrest the Cup from St Helens' iron-like grip.

The only other alternative open to Agar would be to switch Shaun Berrigan, the former Australia Test hooker, to scrum-half with Danny Broughton and Tommy Lee sharing the hooking role.

Agar must also decide who to opt for at full-back following the loss of New Zealander Motu Tony, who suffered a knee ligament strain in last Friday's 26-6 victory over Harlequins.

Australian veteran Matt Sing is likely to return from a thigh strain to play at full-back with his fellow countryman Todd Byrne starting at centre, a move that would see 18-year-old Tom Briscoe crown a memorable first year at senior level with a starting place on the wing.

As well as Sing, Hull will welcome back Garreth Carvell on Saturday after the prop, who continues to be linked with a move to St Helens, was rested last Friday.