Ruben Moloney, Andrew Sparrow and Ciarán Mangan will make their first Leinster starts in Saturday's BKT URC clash against Edinburgh.
Missing their Ireland contingent, Leinster have named a youthful side for the visit of the Scots to Aviva Stadium (5.30pm).
Luke McGrath captains the team from scrum-half while Charlie Tector swaps into the number 10 shirt following his player of the match performance in the win over Connacht last Saturday.
Ciarán Mangan is set to make his first start after a debut cameo off the bench against Zebre Parma back in October, with Rieko Ioane his partner in the centre.
Moloney will also make his first senior start, with Joshua Kenny on the opposite wing and Andrew Osborne at full-back.
Sparrow at tighthead prop is another who will make his first start, with John McKee at hooker and Jerry Cahir set to scrum down on the loosehead side.
RG Snyman will partner Brian Deeny in the second row, with Max Deegan and Scott Penny on the flanks and Diarmuid Mangan packing down at number 8.
After making his debut last week, Niall Smyth is named among the replacements with Gus McCarthy and Alex Usanov providing the rest of the front row cover.
Conor O'Tighearnaigh, Josh Ericson and Will Connors offer their reinforcements as part of a 6:2 split, with Fintan Gunne and Hugo McLaughlin completing the bench.
Leinster: Andrew Osborne; Joshua Kenny, Rieko Ioane, Ciarán Mangan, Ruben Moloney; Charlie Tector, Luke McGrath (capt); Jerry Cahir, John Mckee, Andrew Sparrow; RG Snyman, Brian Deeny; Max Deegan, Scott Penny, Diarmuid Mangan.
Replacements: Gus McCarthy, Alex Usanov, Niall Smyth, Conor O'Tighearnaigh, Josh Ericson, Will Connors, Fintan Gunne, Hugo McLaughlin.
Meanwhile, Connacht have made five changes from the side that started against Leinster at Dexcom Stadium for their trip to Zebre tomorrow (3pm Irish time).
With Billy Bohan, Darragh Murray and Cian Prendergast unavailable on Ireland duty, they have been replaced by Jordan Duggan, Niall Murray and Sean O'Brien.
The other changes are the inclusion of Jack Aungier at tighthead prop who replaces the injured Sam Illo, and Chay Mullins on the left wing.
Dylan Tierney-Martin starts at hooker, Josh Murphy is in the second row, with a back row of captain Paul Boyle and Sean Jansen.
Caolin Blade and Josh Ioane continue at 9 and 10, as does the centre partnership of Cathal Forde and Harry West.
The in-form Shane Jennings and Sam Gilbert complete the side in the back three.
The replacements includes three academy players in Matthew Victory, Fiachna Barrett and Sean Naughton, while Oisin McCormack is also named in the matchday squad for the first time this season.
He wears the 23 jersey in a 6:2 split on the bench.
Connacht: Sam Gilbert; Shane Jennings, Harry West, Cathal Forde, Chay Mullins; Josh Ioane, Caolin Blade; Jordan Duggan, Dylan Tierney-Martin, Jack Aungier; Josh Murphy, Joe Joyce; Paul Boyle (capt), Sean O’Brien, Sean Jansen
Replacements: Matthew Victory, Peter Dooley, Fiachna Barrett, David O’Connor, Niall Murray, Ben Murphy, Sean Naughton, Oisín McCormack.
Elsewhere, Ulster's matchday squad to face Cardiff on Saturday evening features six players who have been called up to the Ireland XV side to face England 'A' next Friday at Thomond Park.
Scott Wilson, Sam Crean, Charlie Irvine, Jack Murphy, James Hume and Zac Ward will all hope to put their hands up for selection as they welcome the Welsh side to the Affidea Stadium (7.45pm).
The front row sees two changes from last weekend's 27-22 loss at Scarlets, with Australian international loosehead prop Angus Bell joined by hooker Rob Herring and tighthead prop Wilson.
The second row remains unchanged, with captain Iain Henderson joined by lock Irvine.
In the back row, Matthew Dalton starts at blindside flanker, Marcus Rea makes his first start of the season at openside flanker and David McCann starts at number 8.
In the half-back partnership, scrum-half Conor McKee joins fly-half Murphy.
There are three changes to the backline, with the in-form Ward coming back in to start on the left wing.
In the midfield positions, Ben Carson makes his first URC start of the season at inside centre, joined by Hume at outside centre.
Completing the backline, Ethan McIlroy makes his first start of the season at full-back.
Murphy opts for a 5:3 split among the replacements, with Bryan O’Connor, Lorcan McLoughlin and Ben Moxham all in line for their first appearances of the season.
Moxham makes a welcome return to the matchday 23 after his recovery from an ACL injury sustained back in November 2024.
James McCormick, Crean, O’Connor, Harry Sheridan, and McLoughlin provide the forward cover.
David Shanahan, Jake Flannery and Moxham are the backline options.
Ulster have also confirmed that 21-year-ol Murphy has signed an extension to his contract that will keep him at the province until 2028.
Son of head coach Richie, Jack joined from the Leinster academy in 2024 and has impressed in the out-half role.
Ulster Rugby general manager Rory Best said: "Securing Jack's future was another key contract priority for us. Jack has shown an impressive maturity for his age and has already shown that he can lead our attack from number ten.
"His kicking game is a real point of difference for our style of play and the way we want to put pressure on the opposition.
"The exciting thing about Jack is the potential that he has, and we must continue trying to make the most from his talent over the seasons ahead."
Ulster: Ethan McIlroy; Werner Kok, James Hume, Ben Carson, Zac Ward; Jack Murphy, Conor McKee; Angus Bell, Rob Herring, Scott Wilson; Iain Henderson (capt), Charlie Irvine; Matthew Dalton, Marcus Rea, David McCann.
Replacements: James McCormick, Sam Crean, Bryan O'Connor, Harry Sheridan, Lorcan McLoughlin, David Shanahan, Jake Flannery, Ben Moxham.
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