Girvan Dempsey, a replacement against London Irish last week, joins Isa Nacewa, Jonathan Sexton and new signing Shaun Berne amongst the backs for the trip to Llanelli.
Speaking ahead of Saturday's encounter, Leinster consultant coach Alan Gaffney says that the squad are keen to start the campaign positively against a strong Scarlets outfit.
"The Scarlets have always historically been difficult opponents. I remember playing for Randwick against Llanelli back in 1973 and we were up against most of the Welsh team!," he said.
"Though they've had a lean time of late by their standards, they have bolstered their squad over the summer and still boast of wealth of talent in their backline and in their formidable pack.
"Whenever you face a Llanelli side you know that you will be up against an expansive side with fast backs and a strong group of forwards and this weekend will be no different.
"David Lyons and Simon Easterby are two excellent players in a powerful back row unit. They have lots of experience in the likes of Deacon Manu and Phil John up front, so we will need to match their power up front."
Gaffney added: "Though the result against London Irish last weekend was a disappointment, you use pre-season games as opportunities to try new systems and we got a lot out of the games against Nice and London Irish.
"We have a few areas that need to be addressed, but there were positives, not least the impact of the younger players like Niall Morris, Paul O'Donohoe and Brendan Macken.
"It was good for the returning Churchill Cup players to get a run-out, while the likes of Girvan (Dempsey) also got some much needed game-time after missing the first game due to the birth of his son.
"There's great competition for places all over the park and it will be some contest for players to try and get into the starting line-up each week.
"It all augurs well for the season, but the hard work starts this week. Saturday is a challenge that we are looking forward to."
LEINSTER Squad (v Scarlets): Backs (11) - Shaun Berne, Girvan Dempsey, Shane Horgan, Chris Keane, Simon Keogh, Brendan Macken, Fergus McFadden, Niall Morris, Isa Nacewa, Paul O'Donohoe, Jonathan Sexton
Forwards (13) - Leo Cullen (capt), John Fogarty, Cian Healy, Bernard Jackman, Shane Jennings, Stephen Keogh, Ronan McCormack, Kevin McLaughlin, Sean O'Brien, Malcolm O'Kelly, Mike Ross, Devin Toner, Stan Wright.