Prop Brett Wilkinson has recovered from the hamstring injury that ruled him out of Rugby World Cup contention. The 27-year-old loosehead, who has earned 118 caps for Connacht to date, replaces Denis Buckley on the bench.
Meanwhile, the Ireland Under-20-capped Stewart Maguire will be hoping to make his first competitive appearance for the province. He comes in for Dylan Rogers as the reserve tighthead prop.
Looking forward to his side's first outing at the redeveloped Sportsground, Elwood said: "The expectations are there, there is pressure, there's a buzz around Galway, Season Ticket sales are up, the new stand is taking shape and people are looking forward to it.
"But it's the pressure we want, we want to be there, we want to be playing the best, competing at the highest level. We're trying to build the brand and a lot of work has gone in on and off the pitch.
"We're hoping people will come and roar and help us on the field with support from the terraces."
Reflecting on the opening victory in Italy, he added: "I'm absolutely delighted with the win against Treviso last time out. It was our first game against a team that doesn't lose that often at home - they won eight out of 11 home games last season.
"So we showed great character and resilience. They're very physical but I was happy with the way we defended the set pieces and driving maul. We didn't allow them to score a try, which was also pleasing."
CONNACHT (v Scarlets): Gavin Duffy (capt); Mark McCrea, Eoin Griffin, Henry Fa'afili, Tiernan O'Halloran; Matthew Jarvis, Frank Murphy; Ronan Loughney, Adrian Flavin, Rodney Ah You, Michael Swift, Mike McCarthy, John Muldoon, Ray Ofisa, George Naoupu.
Replacements: Ethienne Reynecke, Brett Wilkinson, Stewart Maguire, Thomas Anderson, Johnny O'Connor, Paul O'Donohoe, Niall O'Connor, Brian Tuohy.