Saints - playing at Anfield in a wholly admirable attempt to broaden their support - might have Wembley in the back of their minds, but they are still likely to show Raper, who arrived from Australia on Thursday, how wide is the gulf between the top and bottom of Super League.
"I will only have had one session with the players, so I certainly can't promise any miracles," Raper said. "But if I can put a bit of enthusiasm into them we can give Saints a run for their money."
With Alan Hunte struggling to recover from a hamstring tear in time for the Challenge Cup final, Andy Haigh makes his first start of the season and has a chance to put himself in the frame for Wembley.
The other Cup finalists, Bradford, are the only unbeaten team in Super League on either side of the world, but that does not mean that their coach, Matthew Elliott, has been happy with their recent performances.
The Bulls scraped home against Halifax on Wednesday, prompting Elliott to say: "That's three games in a row where we haven't played at all well. We won't keep getting away with it."
Sheffield Eagles beat Bradford during the run-up to Wembley last year and Graeme Bradley, the Bulls captain in the absence of Robbie Paul, warns that they could do so again unless his side lift their game.
The Bulls will be helped by the return from injury of Stuart Spruce and Paul Medley and, from suspension, of Brian McDermott.
Sonny Nickle will test out his arm, while a decision will be made tomorrow morning on whether Robbie Paul should play a few hours after his return from playing for New Zealand in Sydney. Paul scored a try in an impressive international debut, but could not prevent a 34-22 defeat by Australia.
Bob Lindner, lined up to take become director of coaching at Oldham, has arrived from Australia but will not be taking on an official role until be obtains a work permit and agrees terms. The captain, Martin Crompton, has picked the side to face Halifax on Sunday.
London Broncos have Tony Mestrov, Robbie Beazley and Scott Roskell back in action against an unchanged Leeds, while Tony Blair will kick off at Warrington's game against Paris. Given the club's search for new blood, the offer of a contract is not out of the question.Reuse content