Harry Robinson returns to the Arms Park for the first time since his move down the M4 motorway, and Lou Reed and Josh Turnbull start for the Blues against their former region.
Reed is one of five changes made by Director of Rugby Mark Hammett as Blues target a third win of the season in the league.
Argentina international duo Lucas Amorosino and Joaquin Tuculet, who scored a spectacular try on his debut for the region against Benetton Treviso last month, both earn recalls after missing European action.
Scrum half Lewis Jones will partner Gareth Anscombe at half back, with Lloyd Williams missing the game through injury. Hooker Kristian Dacey is also named in the front row alongside captain Gethin Jenkins and Adam Jones.
Pivac’s men have not lost a game in the Guinness PRO12 at Parc y Scarlets this season but are yet to secure a victory on the road, a 20-20 draw against Edinburgh has been the only away result. Scarlets were defeated 8-14 at Connacht in round 9 and have not lost back-to-back Guinness PRO12 encounters since.
Steffan Evans starts for the Scarlets in the absence of Liam Williams, but Jake Ball has recovered from a virus to start.
Hammett said: “We’re all looking forward to the game and the battle of ‘East versus West’.
“It will be a new experience for me and my first taste of a festive Welsh derby. But I’ve heard all about the big crowds and the fantastic atmosphere these games generate. We now need to harness that emotion and energy to help us perform.
“Scarlets secured an impressive European win over Ulster Rugby last weekend and are powerful side that plays with real aggression.”
Pivac said: “Every new opposition is a new experience for me here and I’m enjoying it. On paper they’re a very good side, don’t think they’ve performed to the best of their ability. We need to stay focused and discipline is what we’ll need. We’ll have to be at the top of our game.
“It’s a massive game. They still have ambitions in the competition; there’s pressure to get results for all coaches and all teams.”