Scarlets have won four of the last five contests against Ulster in the Magners League, and won at Ravenhill for the first time in league play on their most recent visit on 5 September 2008.
Ulster won 30-6 at Connacht on Friday but have not won successive Magners League games for almost 12 months. The Ulstermen are struggling at home just now, having slipped to three consecutive defeats. Ulster won 20-16 the last time they played a Welsh team: Ospreys at Liberty Stadium in round two.
Scarlets have recorded three successive losses but at least have picked up a losing bonus point in the last two. The Welshmen's only away win in the Magners League since early January was 30-9 at Cardiff Blues on 13 May.
Referee: Peter Allan (SRU, 31st League game).
Assistant Referees: D Phillips (IRFU), B O'Keeffe (IRFU).
TMO: Marshall Kilgore (IRFU).
Live on BBC Cymru and Setanta Sports