Forgotten star of the 2013 British and Irish Lions tour, Dan Lydiate, will lead Ospreys for the third time this season when they take on Leinster.
Follow all the action on the RugbyPass live blog from the Guinness PRO14 match between Ospreys and Ulster at Liberty Stadium.
A try from outside-half Jarrod Evans helped Cardiff Blues register their first win in Swansea for 14 years as the Ospreys woeful form continued with a 19-16 Guinness PRO14 Welsh derby defeat at the Liberty Stadium.
Just 37 seconds were on the clock in Swansea when referee Frank Murphy gave the Welsh team's full-back his marching orders for four play.
Ospreys full-back Dan Evans received one of the quickest red cards in professional rugby union history as his team lost 40-19 against Heineken Champions Cup opponents Racing 92.
Munster opened their Heineken Champions Cup campaign with a 32-13 bonus point victory over Ospreys at the Liberty Stadium.
Ospreys replacement fly-half James Hook missed two late penalties as Southern Kings hung on to register a 16-14 victory – their first Guinness Pro14 win of the season.
Ospreys Rugby have confirmed that Hanno Dirksen has signed a new two-year deal with the Region, making him the 16th member of the senior squad to re-sign in 2019.
Ospreys booked their place in the Heineken Champions Cup by winning a close-fought Guinness PRO14 play-off against Scarlets 21-10 at the Liberty Stadium.
Cardiff Blues have picked Gareth Anscombe for the Judgemnent Day clash against the Ospreys which is effectively a two-team shootout for a Heieneken Champions Cup playoff place.
