The Ospreys are sitting pretty in second place in the table knowing that victory over The Dragons at Abertillery Park will secure their place in the April 29th final.
However, The Dragons who lost the fixture between the two sides earlier in the season can keep alive their slim hopes of qualification by gaining a second win of the season.
Meanwhile the Scarlets can make sure of their place in the final if they do the double over the Blues. The Scarlets were 30-26 winners when the sides met in November and with home advantage in their favour, they will fancy their chances of adding a fourth win in five games.
Scarlets v Blues (Narberth, 7.15) Dragons v Ospreys (Abertillery 7.15)