Along with Roux, Jake Heenan makes a welcome return from injury and his first appearance of the season.
Dillane starts in the back row for the first time along with Heenan and captain John Muldoon.
Commenting on the team selection and the upcoming game, Pat Lam said:
"With more guys coming back from injury, it's pleasing to be able to select a bit more experience in our side. Quinn (Roux) and Jake (Heenan) returning is obviously a boost and it helps drive more competition within the squad.
"Although we have never won at Parc y Scarlets before, we are really excited by the challenge to try and create a small bit of history.
"While both teams are obviously determined to get points on the table, our focus remains on the quality of our performance."
Connacht team to face Scarlets, Saturday 24th September, Parc y Scarlets, 7:35pm
(Connacht caps in brackets)
15 Tiernan O'Halloran (103)
14 Niyi Adeolokun (34)
13 Bundee Aki (43)
12 Eoin Griffin (73)
11 Matt Healy (75)
10 Jack Carty (56)
9 Kieran Marmion (104)
1 Denis Buckley (97)
2 Tom McCartney (46)
3 Finlay Bealham (59)
4 Quinn Roux (33)
5 Andrew Browne (144)
6 Ultan Dillane (29)
7 Jake Heenan (34)
8 John Muldoon (captain) (277)
Replacements:
16 Dave Heffernan (59)
17 Ronan Loughney (185)
18 JP Cooney (30)
19 Lewis Stevenson (2)
20 Eoin McKeon (87)
21 Caolin Blade (22)
22 Shane O'Leary (16)
23 Cian Kelleher (1)
Injured/Unavailable: Nathan White, Dominic Robertson-McCoy, Ivan Soroka, Saba Meunargia, Ben Marshall, Nepia Fox-Matamua, Sean O'Brien, Eoghan Masterson, John Cooney, Conor Lowndes, Craig Ronaldson, Marnitz Boshoff, Peter Robb, Rory Parata, Josh Rowland, Danie Poolman, Darragh Leader, Ciaran Gaffney.
Scarlets v Connacht
Saturday 24th September 2016
At Parc y Scarlets, 7.35pm.
Live on S4C/TG4
Referee: George Clancy (IRFU, 83rd competition game)
Assistant Referees: Keith Allen (SRU), Leighton Hodges (WRU)
Citing Commissioner: Ray Wilton (WRU)
TMO: Jim Yuille (SRU)
Guinness PRO12 Connacht News
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