Roby and Wellens have won the last two Man of Steel awards

Roby, 21, has agreed a new four-year deal, which is set to keep the reigning Man of Steel at the club until the end of the 2011 season.

Wellens, 27, has put pen to paper until 2010 as Saints continue the policy of tying star names to new contracts.

"They will be our backbone as we signal our intention to win even more," said Saints chairman Eamonn McManus.

Wellens, Roby's predecessor as Super League's Man of Steel, has become an automatic chance for club and country at full-back.

606: DEBATE I'm a big Saints fan and I think it's wonderful news that they have both have signed new deals kenored

Both Wellens and Roby played significant roles in Great Britain's 3-0 series whitewash over New Zealand in October and November.

"I'm sure this announcement will come as a great early Christmas present for all Saints fans," added McManus.

"There was significant interest in James, which is understandable as he is one of the hottest properties in the game, and we are delighted to have secured his services for another four years.

"Paul has established himself as the best full-back in the game and will continue to play a pivotal role as the club moves forward.

"Not only have both players come through our Academy system, which shows its strength, but both have become an integral part of the club's success as well as being excellent ambassadors for St Helens."

Earlier this year, St Helens agreed contract extensions with Jon Wilkin, James Graham, Ade Gardner, Sean Long, Keiron Cunningham and Maurie Fa'asavalu.