Stones, part of the giant Bass Brewers group, is withdrawing from its sponsorship two years into a three-year deal, leaving the competition with the task of finding a new backer in time for next season.
The brand -a draught and canned bitter brewed in and primarily associated with the north of England - has been heavily involved with the game for 11 years, sponsoring what was then the Rugby League Championship for nine seasons and then continuing its support for the first two seasons of Super League.
It has also sponsored the end-of-season Premiership play-offs and the leading individual awards for players and coaches, a total package now worth almost pounds 600,000 a season to the game.
Although that shrinks by comparison with the investment on behalf of another Bass brand, Carling lager, in football's FA Premiership, it is big money for rugby league; to lose it a year ahead of schedule is a major blow.
Neither Stones nor the Rugby League would comment yesterday, as they made preparations for the presentation of the championship trophy to the Bradford Bulls at Odsal last night, but an announcement is planned for early next week.
That announcement will be couched in amicable terms, but it is understood that the League believes that the apparent fragmentation of the game over recent months has played a part in the company's decision.
The 12 Super League clubs have, as of this season, their own marketing organisation, Rugby League (Europe), whose priority must now surely be to secure new sponsors to fill the void when Stones bow out after the Premiership final at Old Trafford in September.Reuse content