Wellens and Pryce will spearhead the resistance to Rhinos' charge

Some at Leeds might try to deny it, but this season's priority has always been the Challenge Cup.

Beaten in the World Club Challenge and slightly off the pace in Super League, which they have monopolised over the past three years, today's semi-final against St Helens assumes an extra significance.

Set against their success in Grand Finals, the 11 years since they won the Cup or even played at Wembley looks and feels like an unconscionable length of time. Thus Kevin Sinfield, the Leeds captain for most of the intervening period, is unable to compare the two competitions.

"I can't tell you how good it would feel to win the Cup, because I've never won it," he says. "I can tell you what winning a Grand Final feels like."

One Leeds player who does know what victory at Wembley feels like is Keith Senior, a member of the Sheffield Eagles side that beat Wigan against all the odds in 1998, and he could have a key role to play in his native Huddersfield today.

With Carl Ablett suspended and Greg Eastwood and Ali Lauitiiti injured, Senior could be required to play all or part of the game in the second row, a switch for which he has long looked destined but one he has largely avoided up to now. That would free up a place in the centres for Lee Smith, who, despite the unevenness of his contribution since his return from his brief exile in rugby union, has the look and the record of a big-match player.

Anyone playing in the Rhinos' pack can expect a ferocious pep-talk from Jamie Peacock, ratcheted up a notch from his animated address when they played Warrington.

"You couldn't have printed much of what I said that day and I should think I'll be that bit more fired up for a semi," he says, with the air of a man set on leading by example.

Not that Saints will lack motivation. Although their form, like Leeds', has been full of peaks and troughs, last week's win over Warrington suggested that they are hitting their best at the right time. Apart from the eternal lure of Wembley, they have a number of factors pushing them in the right direction.

Discarded internationals Paul Wellens and Leon Pryce want to show that they are still the best in their positions, the whole side wants to give Keiron Cunningham a suitable send-off and Mick Potter, despite playing it cool, does not want to be remembered as the first St Helens coach of the Super League era to finish his stint without silverware.

A few weeks ago, the outcome of tomorrow's other semi-final between the holders, Warrington, and the Catalan Dragons looked, even allowing for the vagaries of the Cup, close to a foregone conclusion.

Since then, however, the Wolves have suffered a couple of defeats that have reawakened doubts about their ability to win big matches, while the Catalans have had a couple of morale-boosting victories that have lifted them off the foot of the Super League table.

"We've got the strongest squad we've had available all season, so that's a good sign," said their coach, Kevin Walters, who returned on Tuesday from his father's funeral in Australia.

Casey McGuire, Clint Greenshields, Dallas Johnson and the former Warrington prop, Jerome Guisset, are all fit to play at Widnes tomorrow.

Another prop, David Ferriol, has denied comments attributed to him in a newspaper to the effect that Warrington's Adrian Morley is "past it".

"A mistake has been made somewhere," he said. Ferriol is no shrinking violet, but he may well think so the first time he clashes with Morley.

The Wolves captain is one who has emphasised how desperate they are to hang onto their trophy, having waited so long to win it last year.

Mickey Higham and Chris Bridge are still out and Simon Grix is recovering from viral pneumonia but, otherwise, Warrington are at full strength.

From a purely financial point of view, the game needs them to get to Wembley and guarantee a full house.

The key to doing that could be their wild card, David Solomona, who has been so adept this season at coming off the bench and turning a tight match with an uncanny pass.