Munster, having already secured the title, will be presented with the trophy after Friday's game at Thomond Park Stadium.
Their opponents, the Ospreys saw their own title hope fade after a home defeat by Edinburgh, but they will still want to put on a good show having not won on Munster soil since February 2004.
The other game on Friday sees Glasgow Warriors welcome Connacht to Firhill Arena. Both teams will be determined to end a poor run with a morale-boosting victory in this final fixture.
Saturday sees another televised double header, with the two host teams, the Scarlets and Newport Gwent Dragons, possibly still battling to avoid the Heineken Cup play-off game.
The Dragons' opponents, Leinster, will surely have their eye on their Heineken Cup final the following week, whilst a visit to Parc y Scarlets should hold no fear for Ulster, whose away form has been better than their home form of late.
The last game of the round is appropriately the last competitive game the Cardiff Blues will play at the Arms Park before their move to the new stadium they will share with Cardiff City next season.
Edinburgh will have their work cut out if they aim to spoil this leaving party. Already assured as the top Scottish team, Edinburgh could finish as high-placed as second if other results go their way.
MAGNERS LEAGUE - ROUND 18 FIXTURES:
ROUND 13 (Refixed game):
Wednesday, May 13 -
Cardiff Blues v Scarlets, Arms Park, 7.35pm (live S4C)
Friday, May 15 -
Glasgow Warriors v CONNACHT, Firhill Arena, 7.45pm (live Setanta Sports 1)
MUNSTER v Ospreys, Thomond Park Stadium, 7.45pm (live Setanta Sports Ireland/Setanta Sports 2/BBC Wales)
Saturday, May 16 -
Newport Gwent Dragons v LEINSTER, Rodney Parade, 5.30pm (live Setanta Sports Ireland/Setanta Sports 2/S4C)
Scarlets v ULSTER, Parc y Scarlets, 7.30pm (live Setanta Sports 2/S4C)
Sunday, May 17 -
Cardiff Blues v Edinburgh, Arms Park, 3.35pm (live S4C)