Martin Offiah believes St Helens must emerge triumphant from their "battle royal" with Leeds at the weekend to prevent any further damage to their legacy - and feels the stage is set for Sean Long to make an inspirational impact.

The two Super League giants collide in the Grand Final at Old Trafford on Saturday for the third season on the trot and Saints will be desperate for revenge having lost the previous two against their fierce rivals.

On both occasions they headed into the showpiece finale as favourites having topped the table during the regular season but it was the second-placed Rhinos who marched away with back-to-back titles as supposed underdogs.

Now the roles are reversed with Brian McClennan's Leeds side hotly fancied to clinch a historic hat-trick of successive Super League crowns - and fourth overall - following a stunning end-of-season surge which saw them win 11 of their last 12 matches to storm away with the League Leaders' Shield.

Saints by contrast lost five of their last nine league games, including an 18-10 defeat at Headingley Carnegie in the penultimate match of the season, as well as suffering Challenge Cup semi-final heartache at the hands Huddersfield but they managed to make amends with play-off victories over the Giants and Wigan to reach the Grand Final for the sixth time in their history.

Rugby league legend Offiah, now a leading pundit and agent in the game, is in no doubt St Helens deserved more than the solitary Grand Final triumph to show for their dominance in Super League over the previous four seasons, in which they topped in the table in each of them, and feels they can't afford to lose again this time.

"It's the fourth Grand Final in a row which St Helens have been in but they've lost the last two and it's perhaps ironic this time it's Leeds who are the favourites," said Offiah, speaking ahead of the launch of his new book 'Martin Offiah's 50 Of The Best' next month.

"The Rhinos have been pretty phenomenal recently, they topped the table and even beat St Helens in the penultimate game of the season.

"St Helens on the other hand do have some great players and have been trying to work their way back into form - even though the form guides can go out of the window when it comes to big occasions like the Grand Final.

"I truly believe St Helens have been the best team in rugby league over the last four to five years but losing two Grand Finals have really hurt their legacy.

"If they had won those two games, and again on Saturday, they would have gone down in history as the best and most dominant rugby league team of all time - without a shadow of a doubt.

"But having lost those two games, if they taste defeat again Saturday then that will really damage their legacy."

Offiah is expecting a rip-roaring tit anic showdown, packed full of aggression, passion and drama but he doesn't think St Helens are the only team with something to prove.

He said: "In the last meeting between the teams at Headingley Jon Wilkin got decked by Keith Senior and James Graham got chicken-winged by Jamie-Jones Buchanen - so there's bound to be a lot of needle in this game. Especially because Saints have been beaten twice in the last two finals when being favourites.

"Saints are sure to want to knock Leeds off their perch but the Rhinos also have a chip on their shoulder.

"They know a lot of people in rugby league say they weren't the best team over the previous two seasons, despite winning two Grand Finals. I mean if Catalans Dragons had won last weekend and then went on to win the final, we wouldn't be saying they are the best team in rugby league.

"That's the way the system is, it's exciting for the fans and no one knows which way it will go. But that is why Leeds have a chip on their shoulder this season because they want to prove their are the best team."

Long, who kicked his 1,000th goal for St Helens back in February, will be playing his last match for Saints after an illustrious 12-year spell at Knowsley Road and Offiah believes it would be the perfect end if the scum-half can claim the Harry Sutherland Trophy prior to his move to Hull FC next season.

Offiah said: "I know there's no room for sentiment in sport but it seems set up for Sean Long to leave St Helens on a high at Old Trafford and I'm sure he'll be desperate to get that win.

"But there's plenty of others stars on show. Kyle Eastmond is a young, exciting player who has really grown in prominence over the second half of the season and is the natural replacement for Long next year.

"James Graham must obviously have a huge performance up front and his battle with Jamie-Jones Buchannon and Jamie Peacock will really be worth the price of admission.

"For Leeds I think Danny McGuire is coming into form just at the right time and he has a great try-scoring record at Old Trafford while Keith Senior and Ryan Hall have both had great seasons.

"Overall it would be fitting if Sean Long could win that Harry Sutherland Trophy but there's no room for sentiment in sport and the stage could be set for someone new like Eastmond or Ryan Hall."

Other pundits have predicted the end of an era for St Helens, whether they win or lose on Saturday, and while Offiah believes Saints are well capable of re-launching themselves, he agrees they've had to inevitably make way for the charging Rhinos to dominate.

He said: "Saints have gone through a transitional season anyway - they've had no Paul Sculthorpe for the first time following his retirement and now they know Sean Long and Lee Gilmoor will be going too.

"Paul Wellens and Keiron Cunningham can't be far behind either - I can imagine them both having one more season maximum left at Saints - so this is a transitional period for sure.

"It's time for Gary Wheeler, Kyle Eastmond and Paul Clough to stand up and take over while the big Kiwi centre Sia Soliola will be coming over for 2010. They really have missed a left centre all season - they've tried Gilmoor there, Wheeler there and Eastmond there but it hasn't worked out as well as it could have.

"Considering this is a transitional time for Saints, they haven't done too badly. They were one game from Wembley in the Challenge Cup and are once again in the Grand Final for the fourth time in a row - so there's no reason for them to be downbeat really.

"Leeds on the other hand have been maturing as a team over the past few seasons and the likes of Kevin Sinfield, Danny McGuire, Rob Burrow and Matt Diskin are at their peak so it's naturally their time to dominate Super League.

"But no team can be dominant forever though."

When Warrington beat Huddersfield to lift the Challenge Cup at Wembley earlier this season, it was the first final since 1998 without the presence of either Leeds or St Helen s but Offiah insists the Super League Grand Final isn't a stage for anything less than the two true best teams.

He said: "To see two new teams in the Challenge Cup was very refreshing and it really felt as if the spirit of Wembley was finally back as a major showpiece occasion. It is a fairytale and romantic.

"But I think with the Grand Final we still want to see the two best teams there and that's why I feel it was necessary for both St Helens and Leeds to book their places at Old Trafford.

"The Grand Final isn't about fairytales, it's all about the two best teams getting there and slugging it out in an almighty battle to see who is the best. And if they are the best teams, then that's what we want to see.

"I think it's fitting that Leeds and St Helens are in the Grand Final and I really expect an awesome encounter - a battle royal."