12 Dec, 14:42
Prop Cian Healy is expected to miss the start of the 2014 RBS 6 Nations after undergoing surgery on his injured ankle on Wednesday.
Rob Herring and Adam Macklin are retained in the front row, while Tom Court starts at loosehead prop. Dan Tuohy makes his first start after recovering from a torn calf muscle and joins Lewis Stevenson in the second-row.
Chris Henry will captain the table-topping Ulstermen from openside flanker, with Robbie Diack selected on the blindside and Nick Williams lining out at number 8.
Callum Black drops to the bench along with fellow forwards Neil McComb and Roger Wilson. Paddy Wallace and John Afoa should see action as replacement with youngsters Niall Annett, Michael Heaney and Ricky Andrew also kept in reserve.
The eagerly-awaited match, which is sold out, will see leaders Ulster take on the team immediately below them in the table, the Simon Easterby-coached Scarlets.
Meanwhile, a limited number of tickets are still available for Ulster's Heineken Cup round 5 game against Glasgow Warriors at Ravenhill on Friday week and are available at SS Moore's only.
ULSTER (v Scarlets): Adam D'Arcy; Andrew Trimble, Darren Cave, Luke Marshall, Craig Gilroy; Paddy Jackson, Ruan Pienaar; Tom Court, Rob Herring, Adam Macklin, Lewis Stevenson, Dan Tuohy, Robbie Diack, Chris Henry (capt), Nick Williams.
Replacements: Niall Annett, Callum Black, John Afoa, Neil McComb, Roger Wilson, Michael Heaney, Paddy Wallace, Ricky Andrew.