Justin Tipuric will captain Wales and Scarlets wing Johnny McNicholl is to make his first appearance against the Barbarians in Cardiff on Saturday.
Cardiff Blues half-backs Tomos Williams and Jarrod Evans link up with Hadleigh Parkes and Owen Watkin partnered in midfield. Uncapped McNicholl will line-up in a back three alongside Josh Adams and Leigh Halfpenny.
Former Scarlets boss Pivac, who has succeeded his fellow New Zealander Warren Gatland, said: "This week has been hugely exciting and hugely important for us as a group.
"It has been an opportunity for us as a new squad and management to get together and to set the scene for what the future holds.
"There has been quite a lot of learnings for the squad this week, looking at what we are trying to do and us providing some clarity but we have also stressed the enjoyment factor of being together for the first time and the excitement of not only this weekend but the future."
Former Ireland captain Rory Best will captain the Barbarians team.
France centre Mathieu Bastareaud lines up in midfield alongside South Africa's Andre Esterhuizen, while Curwin Bosch and Bryn Hall are the half-backs.
Barbarians head coach Gatland is making an emotional return to Cardiff after ending his 12-year stint with Wales earlier this month.
"It's been a great experience, getting to know players I've not worked with before," Gatland said. "The guys have bonded and had a bit of fun, as well as getting serious as well.
"I'm just looking forward to Saturday. It's a great opportunity for me to say thank you to the fans and the Welsh public for 12 brilliant years."