Magners has extended its sponsorship of the Celtic rugby union league for a further two years.
The agreement will see Magners continue as title sponsor of the competition until May 2011. It began the sponsorship in 2006.
"Our relationship with Celtic Rugby has been productive and rewarding over the last three years and we are delighted to be extending our partnership," said Magners marketing director Stephen Kent.
"Since the first year of sponsorship the stature of the Magners League has increased significantly — the next two seasons will mark a new stage in the development of the tournament, particularly with the introduction of season ending playoffs and we are excited about the prospect of being involved in this process."
David Jordan, director of Celtic Rugby, added: "The support and enthusiasm that Magners has shown in partnering and investing in our league has been self evident to all our stakeholders.
"In the three years since Magners have come on board we have seen a dramatic increase in attendances at matches and a substantial improvement in the competitiveness and attractiveness of our tournament."