After a nail biting victory in Aironi, the Ospreys now travel to Ireland to play Munster at Thomond Park on Saturday 14 May (kick off 6.30pm).
In the other semi final in an all Ireland clash Leinster will host Ulster at RDS in Dublin on Friday 13 May (kick off 7.05pm).
The winners of the Play-Off matches, which will be played at the home venues of the top two finishing sides in the regular Magners League table, will then meet in the Magners League Grand Final on Saturday, 28 May (Kick-Off 17:05).
The venue of the second Magners League Grand Final will be determined by the results of the semi-finals. The honour of staging the Grand Final will go to the team that has the highest regular season league ranking once the two finalists are known ie Munster if they win their game or the winners of the second semi-final.