Dan Sheehan will make his first appearance since last summer when Leinster host Stormers on Saturday in the BKT United Rugby Championship.
The Ireland hooker, who has recovered from an ACL injury, will captain the side in Aviva Stadium for the 5pm kick-off, while fellow international James Lowe returns from a calf injury suffered at the end of November.
While most of the senior players are in Portugal for Ireland's Six Nations training camp, Leo Cullen is able to call upon New Zealand’s Jordie Barrett, South Africa’s RG Snyman and France’s Rabah Slimani.
With Lowe on the left wing, McErlean and Andrew Osborne complete the back three, while Luke McGrath and Ross Byrne pair up at half-back.
In the pack, Slimani and Max Deegan keep their places in the starting XV from the side that beat Bath in the Champions Cup, although the latter shifts over from flanker to number 8.
Jack Boyle joins Slimani and Sheehan in the front row, with Snyman and Brian Deeny offering the support from the second row.
Alex Soroka and Scott Penny have been named on the flanks as league leaders Leinster bid to add to their 13-game winning run.
Will Connors has recovered from a hamstring injury and starts among the replacements.
Leinster: Henry McErlean; Andrew Osborne, Liam Turner, Jordie Barrett, James Lowe; Ross Byrne, Luke McGrath; Jack Boyle, Dan Sheehan (capt), Rabah Slimani; RG Snyman, Brian Deeny; Alex Soroka, Scott Penny, Max Deegan.
Replacements: John McKee, Paddy McCarthy, Rory McGuire, Diarmuid Mangan, James Culhane, Will Connors, Cormac Foley, Charlie Tector.
Meanwhile, Munster have confirmed that Mikey Haley has undergone ankle surgery but not specified how long they will be without the full-back.
The province have made six changes to their team to take on the Dragons at Rodney Parade on Saturday evening (7.35pm, live on RTÉ).
Ian Costello's men lost narrowly to Northampton in the Champions Cup last weekend and are without Tadhg Beirne, Jack Crowley, Conor Murray, Calvin Nash and Peter O’Mahony, who are on international duty.
Four academy players are included with full-back Ben O’Connor making his first start for Munster on his eighth appearance for the province.
Academy hooker Danny Sheahan is included among the replacements and set for his senior debut.
O’Connor, Shane Daly, after completing return-to-play protocols, Billy Burns and Ethan Coughlan come into the backline with Tom Ahern and captain Jack O’Donoghue starting in the pack.
It will be a first URC appearance with Munster for Kilgallen after his two-try competitive debut for the province in the Champions Cup last week.
Rory Scannell and Tom Farrell continue their centre partnership for the fourth successive game with Coughlan and Burns in the half-backs.
Dian Bleuler, Diarmuid Barron and Oli Jager pack down in the front row with Fineen Wycherley and Tom Ahern in the engine room.
O’Donoghue, Alex Kendellen and Gavin Coombes start in the back row.
Munster: Ben O’Connor; Diarmuid Kilgallen, Tom Farrell, Rory Scannell, Shane Daly; Billy Burns, Ethan Coughlan; Dian Bleuler, Diarmuid Barron, Oli Jager; Fineen Wycherley, Tom Ahern; Jack O’Donoghue (capt), Alex Kendellen, Gavin Coombes.
Replacements: Danny Sheahan, Kieran Ryan, John Ryan, Evan O’Connell, Brian Gleeson, Paddy Patterson, Tony Butler, John Hodnett.
John Cooney will make his 150th appearance for Ulster in Sunday's clash with Zebre at Kingspan Stadium (5.30pm, live on RTÉ).
Development forward Lorcan McLoughlin will make his first start for the province.
A former Irish U20 Grand Slam winner, this will be McLoughlin’s second senior appearance, having made his debut last season against the Emirates Lions.
With four Ulster players in Ireland camp ahead of the Guinness Six Nations, head coach Richie Murphy has made six changes to the starting lineup that recorded a bonus point win over Exeter Chiefs last weekend to secure a place in the Investec Champions Cup knockout stages.
Cooney will link up with Jack Murphy in a first start together for the half-back partnership.
Zac Ward is the only other change in the backline, returning on the left wing with Michael Lowry switching to the right. Stewart Moore will once again patrol the backfield at full-back.
The 22-year-old duo of Jude Postlethwaite and Ben Carson is retained in midfield, starting together for the fourth game in a row.
Up front, McLoughlin, Tom Stewart, Harry Sheridan and Kieran Treadwell are the changes in the pack.
Stewart will make his first start of the season at hooker, joining Eric O’Sullivan and last weekend’s player of the match Scott Wilson in the front row.
The versatile Sheridan is selected in the second row, where he is joined by Treadwell.
Nick Timoney will captain the side from openside flanker, with McLoughlin named at blindside and David McCann packing down at number 8.
Ulster: Stewart Moore; Michael Lowry, Ben Carson. Jude Postlethwaite, Zac Ward; Jack Murphy, John Cooney; Eric O'Sullivan, Tom Stewart, Scott Wilson; Harry Sheridan, Kieran Treadwell; Lorcan McLoughlin, Nick Timoney (capt), David McCann.
Replacements: John Andrew, Callum Reid, Corrie Barrett, Alan O’Connor, Matty Rea, Nathan Doak, Jake Flannery, Rob Lyttle.
JJ Hanrahan will make his first start in eight month as one of seven Connacht changes for their rescheduled game against Glasgow on Sunday (3.30pm).
The out-half, who returned from a serious knee injuy as a replacement last weekend in the win over Cardiff, will start alongside Caolin Blade at scrum-half.
The forwards see Jack Aungier, David O'Connor, Shamus Hurley-Langton and Sean Jansen all come in.
Peter Dooley and Dave Heffernan make up the front row with Aungier , while Joe Joyce who captains the team partners David O'Connor.
Josh Murphy moves from second row to blindside flanker with Hurley-Langton on the opposite side and Jansen at number 8.
Piers O'Conor will be alongside Hawkshaw in the centre.
The back three remains unchanged with Ralston named on the left wing, Chay Mullins on the opposite side and Santiago Cordero again at full-back. Finn Treacy is in line for a debut off the bench.
Connacht: Santiago Cordero; Chay Mullins, Piers O’Conor, David Hakwshaw, Byron Ralston; JJ Hanrahan, Caolin Blade; Peter Dooley, Dave Heffernan, Jack Aungier; David O'Connor, Joe Joyce; Josh Murphy, Shamus Hurley-Langton, Sean Jansen.
Replacements: Dylan Tierney-Martin, Jordan Duggan, Sam Illo, Oisin Dowling, Paul Boyle, Matthew Devine, Jack Carty, Finn Treacy.
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Watch Dragons v Munster (Saturday from 7.15pm) and Ulster v Zebre Parma (Sunday from 5pm) in the BKT United Rugby Championship on RTÉ2 and RTÉ Player.
