Ireland Under-20s star Sam Prendergast will make his Leinster debut after being handed the out-half jersey for their BKT United Rugby Championship clash with the Emirates Lions (Saturday, 3pm) .
Leo Cullen has send a largely inexperienced side to South Africa with top spot in the table already secured.
Chris Cosgrave starts at full-back.
On the wings, Dave Kearney is set to make his 150th league appearance, while there is a welcome return for Tommy O'Brien, who makes his first appearance of the season after recovering from a knee injury.
In the centre, Liam Turner is joined by Ben Brownlee, with Nick McCarthy partnering Prendergast at scrum-half.
In the front row, Georgia international Vakhtang Abdaladze is set for his first Leinster start. He will pack down with Michael Milne and Lee Barron.
Brian Deeny joins South African international Jason Jenkins in the second row, with Ruddock, Will Connors and Max Deegan forming the back-row.
On the bench, five academy players are set to feature with Alex Soroka, James Culhane, Ben Murphy, Charlie Tector and Rob Russell all looking to impress.
Leinster: Chris Cosgrave; Tommy O'Brien, Liam Turner, Ben Brownlee, Dave Kearney; Sam Prendergast, Nick McCarthy; Michael Milne. Lee Barron, Vakhtang Abdaladze; Brian Deeny, Jason Jenkins; Rhys Ruddock (capt), Will Connors, Max Deegan.
Replacements: Tadgh McElroy, Ed Byrne, Thomas Clarkson, Alex Soroka, James Culhane, Ben Murphy, Charlie Tector, Rob Russell.
Meanwhile, Ireland out-half Joey Carbery has been left out of the Munster squad for their encounter with the DHL Stormers (Saturday, 5.15pm).
Jack Crowley starts at 10 with Ben Healy named on the bench.
Loosehead prop Jeremy Loughman has recovered from a thigh injury and makes his first appearance since December in an all-changed front row.
Hooker Diarmuid Barron and tighthead prop Stephen Archer also come into the pack along with flanker Alex Kendellen.
There is one change to the backline as Conor Murray starts at scrum-half.
RG Snyman makes his second start in-a-row and his first URC start since his Munster debut in August 2020.
Mike Haley starts at full-back with Calvin Nash, who made his 50th appearance last time out, and Shane Daly on either flank.
Malakai Fekitoa and Antoine Frisch continue their centre partnership with Murray and Crowley in the half-backs.
Loughman, Barron and Archer pack down in the front row with Jean Kleyn and Snyman in the engine room.
Captain Peter O'Mahony, Kendellen and Gavin Coombes complete the starting XV.
Scott Buckley, Keynan Knox, Healy and Keith Earls come into the squad as replacements.
Earls is in line for his 199th Munster appearance and his first since the win in Ulster on New Year’s Day after recovering from a calf injury.
Munster: Mike Haley; Calvin Nash, Antoine Frisch, Malakai Fekitoa, Shane Daly; Jack Crowley, Conor Murray; Jeremy Loughman, Diarmuid Barron, Stephen Archer; Jean Kleyn, RG Snyman; Peter O’Mahony (capt), Alex Kendellen, Gavin Coombes.
Replacements: Scott Buckley, Josh Wycherley, Keynan Knox, Fineen Wycherley, Jack O’Donoghue, Craig Casey, Ben Healy, Keith Earls.
Connacht welcome back six players from injury for tomorrow's crucial clash with Cardiff at The Sportsground (7.35pm).
Captain Jack Carty, international Finlay Bealham, Denis Buckley, Jarrad Butler, Josh Murphy and Diarmuid Kilgallen have all overcome injuries to come straight into the starting XV.
Carty has missed the last three games with a hamstring issue, while Bealham hasn’t played since a knee injury sustained in Round 3 of the Guinness Six Nations.
The seventh change from the side that lost to Benetton is the inclusion of Dylan Tierney-Martin, with Eoin de Buitléar named among the replacements.
Connacht: Tiernan O'Halloran; Diarmuid Kilgallen, Tom Farrell, Bundee Aki, Mack Hansen; Jack Carty (capt), Caolin Blade; Denis Buckley, Dylan Tierney-Martin, Finlay Bealham; Josh Murphy, Niall Murray; Cian Prendergast, Conor Oliver, Jarrad Butler.
Replacements: Eoin de Buitléar, Peter Dooley, Dominic Robertson-McCoy, Oisín Dowling, Shamus Hurley-Langton, Kieran Marmion, Tom Daly, Shane Jennings.
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