The Scarlets have lost all three games to date despite running Blues North close in their most recent game at Stradey Park. They lost that contest 14-12 having already been beaten 13-8 by Blues South and 13-0 on the opening day at the Dragons.
In the other game, Blues North will entertain the Dragons at Penycraig after switching the game from Treorchy due to the inclement weather conditions.
The North have been the surprise package this season. Having finished at the foot of the table last season, they have won two of their three games to date. The Blues' high performance manager Gafyn Cooper said, "We have been pleased with the way the North have developed this season. Their two victories have been thoroughly deserved and it would be great to see them make it three in four."