An inglorious one-off or the start of a new career? Dwain Chambers will finally get his chance on a rugby league pitch when he makes his debut for Castleford Tigers in a specially arranged reserve-team fixture against York City Knights on Sunday week that will either make or break the 30-year-old sprinter in terms of a possible playing contract at The Jungle.

The RFL has granted Castleford's request for a money-spinning second-team match, with all the focus on the fast but physically unproven wing with three weeks' training under his belt. Chambers has withstood all that has been thrown at him, including one especially intensive session this week. “It was a bit of a reality check for him, but he's tough mentally. Others would not have finished that session,” Terry Matterson, the Tigers coach, said.

The York match will bring Chambers's month-long unpaid trial to an end and give Castleford some idea of whether they should keep him, although the fact that Matterson considers it too dangerous for him to play in the first team is an indication of where his thoughts lie. Chambers has yet to announce whether he will seek to overturn a ban on him running for Great Britian at the Olympic Games in Beijing in August, but one big tackle could render any decision academic.

St Helens may announce as early as today that Mick Potter, whom Catalans Dragons had hoped to persuade to remain as their coach, will succeed Daniel Anderson from next season. However, Potter said: “It's not cut and dried. I'll do what's best for myself and family.”

Leeds Rhinos, who are joint favourites with St Helens, the holders, for the Carnegie Challenge Cup, begin their campaign at home to Celtic Crusaders in the fourth round this evening. The meeting is a potential Super League fixture next year, if the Bridgend club succeed in their licence application.