Hooker Jason Harris-Wright will earn his 40th cap for the province on Sunday afternoon, starting in a front row with Denis Buckley and last week's try scorer Rodney Ah You.
Galway-man John Muldoon, who has touched down for four tries in the last two games, will captain the side from the back row.
23-year-old Eoin Griffin made an impressive 21 tackles against the Dragons last week and will again partner Dave McSharry in the centre as the team look to record their fifth successive win in the competition.
Commenting on the team selection and the upcoming game, Head Coach Pat Lam said:
"Being able to put out the same team for the third fixture in a row is testament to the performance of those players selected. The recent team performances have been driven by huge competition for places within the squad. Our training has certainly gone up another level in the last number of weeks and we have some experienced and quality players in key positions all pushing hard for a starting place. It makes selection tough in one way but it is also great to see the guys named striving to perform on behalf of the entire squad.
"It's always been a challenge going over to play Scarlets and it's been nearly ten years since we've won at Llanelli. The fact that both sides are now fighting for a top six finish definitely adds some spice. Scarlets have just come off the back of two losses and will see us as a winnable game at home, especially with the amount of internationals they have in their squad. Despite the number of injuries we have, there is a real confidence and belief in our game and the process we need to go through to achieve the different milestones we've set out for ourselves."
Connacht line-up v Scarlets
15. Robbie Henshaw
14. Tiernan O'Halloran
13. Eoin Griffin
12. Dave McSharry
11. Fionn Carr
10. Dan Parks
9. Kieran Marmion
1. Denis Buckley
2. Jason Harris-Wright
3. Rodney Ah You
4. Aly Muldowney
5. Mick Kearney
6. John Muldoon (captain)
7. Eoghan Masterson
8. Eoin McKeon
Replacements:
16. Dave Heffernan
17. Ronan Loughney
18. Nathan White
19. Michael Swift
20. Andrew Browne
21. Frank Murphy
22. Miah Nikora
23. Darragh Leader
Unavailable/Injured: Brett Wilkinson, Sean Henry, James Rael, Craig Clarke, Jake Heenan, Willie Faloon, Aaron Conneely, Paul O'Donohoe, Craig Ronaldson, Matt Healy.
Scarlets v Connacht
At Parc y Scarlets, 2.05pm.
Live on BBCWales / RTE
Referee: Neil Paterson (SRU, 58th competition game)
Assistant Referees: Wayne Davies, Martyn Lewis (both WRU)
Citing Commissioner: Russell Howell (WRU)
TMO: Tim Hayes (WRU)
Follow @ConnachtRugby on Twitter for live match updates.
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