Stephen Ferris, Rory Best, Craig Gilroy and Chris Henry will all start having been rested for last weekend's defeat in Glasgow.
Ulster can also call on prop John Afoa who has returned from New Zealand. The All Black replaces Declan Fitzpatrick who has been ruled out after suffering a neck injury during a scrum against the Warriors.
Best's inclusion at hooker sees Andi Kyriacou drop out of the matchday squad, as Nigel Brady retains his place on the bench. Ferris and Henry join Pedrie Wannenburg in an experienced back row.
Gilroy has been named on the left wing in place of Scotland international Simon Danielli, who misses out on a squad place.
The backs remain otherwise unchanged but Ruan Pienaar is a notable inclusion on the bench, despite not being named in the provisional squad.
The South African scrum half has been ruled out since picking up a hamstring injury against the Scarlets at the end of October.
There are still tickets available for Friday's game. They can be bought online at www.ulsterrugby.com or by calling the ticket office on 02890493222 (ticketing option). Alternatively, you can pay at the gate on match night.
Please be aware that ticket zoning and scanning will be in operation at the ground this season. Supporters should check their tickets to ensure that they are entering through the correct gate. Further details are available here.
Ulster Rugby are advising supporters coming to the game (gates open 5.30pm) to avoid parking in the immediate vicinity of the Ravenhill grounds.
The following roads are only accessible for residents and closed to everyone else:
1. Onslow Parade
2. Ravenhill Park
3. Ravenhill Park Gardens
There will also be parking restrictions in place in the Castlereagh area (Mount Merrion Avenue). Supporters are encouraged to make use of the Park 'n' Ride facilities at Pirrie Park and along Montgomery Road.
ULSTER (v Scarlets): Adam D'Arcy; Andrew Trimble, Darren Cave, Nevin Spence, Craig Gilroy; Ian Humphreys, Paul Marshall; Tom Court, Rory Best, John Afoa, Johann Muller (capt), Dan Tuohy, Stephen Ferris, Chris Henry, Pedrie Wannenburg.
Replacements: Nigel Brady, Paddy McAllister, Adam Macklin, Lewis Stevenson, Robbie Diack, Ruan Pienaar, Paddy Jackson, Ian Whitten.