Joe Westerman's impressive hat-trick helped Castleford Tigers claim a 48-0 victory at Harlequins to book their Super League play-off spot and all but ensure the hosts will not make it.

The two sides began the day with just two points between them but Westerman's heroics left Quins to wonder what might have been.

Brett Ferres, Mitchell Sargent, Dean Widders, Liam Higgins and Kirk Dixon (2) bagged Castleford's other tries but it was Westerman who stole the show.

Bradford remain in the play-off hunt after a 44-18 win over Salford gave them a fourth victory in a row.

The Bulls secured a convincing success thanks to a hat-trick from Chris Nero and Jamie Langley (2), Semi Tadulala (2) and Andy Lynch also touching down for Steve McNamara's side. Mark Henry and John Wilshere (2) bagged tries for the visitors.

A month ago the Bulls looked certain to miss out on the play-offs for the first time but their late-season revival - combined with lapses by Warrington, Catalans Dragons and Harlequins - has breathed new life into their season.

Catalans remain in pole position. However, defeat at St Helens next Friday would open the door for Bradford, Warrington or Harlequins in a tense finish to the season.

On Saturday, Warrington's play-off hopes were severely dented after they were thrashed 40-16 by Hull KR at New Craven Park.

Clint Newton grabbed a hat-trick of tries to condemn the newly-crowned Challenge Cup winners to a heavy defeat with Kris Welham, Paul Cooke, Peter Fox and Jake Webster also touching down for Rovers.

Tyrone McCarthy, Chris Hicks and Mickey Higham bagged tries for Warrington.

Ryan Atkins and Luke George scored two tries apiece as Wakefield halted a Catalans fightback to claim a 34-20 victory.

The Dragons fought back from an 18-10 half-time deficit to lead 20-18 but the Wildcats produced a strong finish to secure a top-six finish with three tries in the final 25 minutes.

Sam Obst also got on the scoresheet while Huddersfield-bound Brad Drew kicked five goals and Danny Brough, on the bench on his return from suspension, added two late on.

Sebastien Raguin and Casey McGuire both touched down twice for the Dragons but the Frenchmen were unable to hold on and they still have work to do in their final game next week to claim a play-off place.

Huddersfield Giants got back to business after their Challenge Cup disappointment as Liam Fulton and Shaun Lunt both touched down twice in an emphatic win 42-16 win over Celtic Crusaders at Brewery Field.

Patrick Larne, Paul Whaturia and David Hodgson also bagged tries for the visitors as they bounced back from last weekend's final defeat against Warrington.

Mark Lennon, Steve Tyrer and Anthony Blackwood touched down for the Welsh side in their final match in Bridgend, where they have been based since their launch three years ago, before heading to Newport for the next two years.

On Friday night, Ryan Hall grabbed a brace of tries as defending champions Leeds beat St Helens 18-10 to put one hand on the League Leaders' Shield held for the last four years by Saints.

Victory in a gripping Grand Final re-match that lived up to all expectations in front of a 19,997 Headingley crowd took the Rhinos two points clear of their arch rivals with one round of the regular season left to play.

It means Leeds need only avoid a heavy defeat in their last match at lowly Salford next Friday to ensure they go into the play-offs in pole position as they seek to wrap up a hat-trick of Super League titles.

The champions' victory owed much to the finishing of Hall, who has enjoyed a tremendous season and took his try tally in all matches to 30 by touching down in each half.

Carl Ablett scored Leeds' other try while Chris Flannery and Lee Gilmour crossed for the visitors.

Amos Roberts and George Carmont scored two tries each as Wigan saw off Hull 34-22 to claim a home tie in the play-offs.

The Warriors were forced to dig deep by a Hull side fighting hard to preserve their own faint top-eight hopes, but Sam Tomkins and Iafeta Paleaaesina ended their post-season aspirations late on.

Hull had briefly led through former Wigan forward Danny Tickle as the game came to life after 30 scoreless minutes, but the Warriors just proved too strong.

Second-half tries from Richard Horne, Tom Briscoe and Craig Hall proved mere consolation as Wigan's eighth win in nine games left Hull with just pride to play for next week.