Munster have received a huge boost for Saturday's must-win Investec Champions Cup tie with Castres, with Craig Casey passed fit to start after overcoming a shoulder injury.
The scrum-half looked to be a long shot to feature this week when he suffered the injury in last week’s defeat to Toulon, after which head coach Clayton McMillan was pessimistic about his chances of being available.
However, the Ireland international’s injury wasn’t as bad as first feared, with Casey fit to take his place in a first-choice side as Munster look to secure qualification for the last 16, joining Jack Crowley in the half-backs.
McMillan has made three changes to his starting side, which will be captained by Tadhg Beirne on his 100th appearance for the province.
Niall Scannell (above) comes in to replace Diarmuid Barron at hooker, where he partners Jeremy Loughman and Michael Ala’alatoa in the front row.
Kleyn returns after missing last week’s defeat to Toulon, and takes the place of Edwin Edogbo at lock, partnering Fineen Wycherley in the second row.
The back row is unchanged, with Beirne at blindside flanker and Jack O'Donoghue on the open side, while Gavin Coombes packs down at number 8.
The other change to the side comes on the right wing, with Thaakir Abrahams brought in for the injured Calvin Nash, while Ben O’Connor is on the left wing and Shane Daly retains the 15 shirt.
Tom Farrell and Alex Nankivell continue their centre partnership, with Dan Kelly available off the bench.
Oli Jager is included among the replacements, with the tighthead prop playing his first game since October after a layoff due to concussion.
Munster: Shane Daly; Thaakir Abrahams, Tom Farrell, Alex Nankivell, Ben O’Connor; Jack Crowley, Craig Casey; Jeremy Loughman, Niall Scannell, Michael Ala’alatoa; Jean Kleyn, Fineen Wycherley; Tadhg Beirne (capt), Jack O’Donoghue, Gavin Coombes.
Replacements: Lee Barron, Michael Milne, Oli Jager, Edwin Edogbo, Brian Gleeson, Ethan Coughlan, JJ Hanrahan, Dan Kelly.
Castres: Theo Chabouni; Christian Ambadiang, Vuate Karawalevu, Jack Goodhue, Geoffrey Palis; Pierre Popelin, Jeremy Fernandez; Atunaisa Sokobale, Loris Zarantonello, Will Collier; Gauthier Maravat, Tom Staniforth; Baptiste Delaporte (capt), Baptiste Cope, Florent Vanverberghe.
Replacements: Teddy Durand-Pradere, Antoine Tichit, Aurelien Azar, Leone Nakarawa, Tyler Ardron, Santiago Arata, Enzo Herve, Atu Manu.
Garry Ringrose, Jimmy O'Brien and RG Snyman return to the Leinster team for Saturday afternoon's trip to face Bayonne in their final pool game.
They are among eight changes to the side that edged out La Rochelle in a last-gasp victory in last week's Champions Cup clash.
Ringrose makes his first appearance since the opening round win over Harlequins, partnering Robbie Henshaw at centre, with Tommy O'Brien and the in-form Joshua Kenny keeping their places on the wings. Meanwhile, O'Brien ends a month-long absence with a spot at full back.
The changes are more extensive in the pack, where Snyman returns to partner James Ryan in the second row. The latter will make his 50th appearance in the Champions Cup in the process.
Max Deegan has been drafted into the starting team, completing the back row alongside Josh van der Flier and captain Caelan Doris.
The front row has been fully reshuffled with Jack Boyle, Rónan Kelleher and Tadhg Furlong in from the start, while Dan Sheehan, Jerry Cahir and Thomas Clarkson provide cover from the bench.
Harry Byrne, who came off the bench last week to convert the winning penalty against La Rochelle, has been rewarded with a start at out-half, forming the half back partnership with Jamison Gibson-Park.
Bayonne: Cheikh Tiberghien; Tom Spring, Sireli Maqala, Manu Tuilagi, Yohan Orabe; Joris Segonds, Herschel Jantjies; Ignacio Calles, Lucas Martin, Junior Tagi; Ewan Johnson, Lucas Paulos; Alexandre Fischer, Arthur Iturria (capt), Nika Lomidze.
Replacements: Facundo Bosch, Emosi Tumania, Emerick Setiano, Alvaro Garcia Iandolino, Baptiste Heguy, Manex Ariceta, Guillaume Martocq, Victor Hannoun.
Leinster: Jimmy O'Brien; Tommy O'Brien, Garry Ringrose, Robbie Henshaw, Joshua Kenny; Harry Byrne, Jamison Gibson-Park; Jack Boyle, Rónan Kelleher, Tadhg Furlong; RG Snyman; James Ryan; Max Deegan, Josh van der Flier, Caelan Doris (capt).
Replacements: Dan Sheehan, Jerry Cahir, Thomas Clarkson, Joe McCarthy, Scott Penny, Luke McGrath, Sam Prendergast, Rieko Ioane.
Bryn Ward (above) will be among the starters picked by Richie Murphy as Ulster as they vie for top spot in Pool 3 of the Challenge Cup against Stade Francais at Affidea Stadium on Saturday.
The 21-year-old joins flankers David McCann and Nick Timoney in the back row, while Wallaby loosehead Angus Bell links up with hooker Tom Stewart and tighthead prop Tom O'Toole in the front row.
In between, Iain Henderson will captain the side as part of a second row partnership with Harry Sheridan.
Nathan Doak and out-half Jack Murphy are the half backs as Ulster return to action after last week's cancelled fixture against Toyota Cheetahs, whilst Zac Ward and Robert Baloucoune are on the wings.
Stuart McCloskey will be at centre alongside James Hume, and fellow Ireland international Jacob Stockdale is named at full back.
Ulster: Jacob Stockdale; Robert Baloucoune, James Hume, Stuart McCloskey, Zac Ward; Jack Murphy, Nathan Doak; Angus Bell, Tom Stewart, Tom O'Toole; Iain Henderson (capt), Harry Sheridan; Dave McCann, Nick Timoney, Bryn Ward.
Replacements: Rob Herring, Eric O'Sullivan, Scott Wilson, Matt Dalton, Sean Reffell, Conor McKee, Jake Flannery, Jude Postlethwaite.
Stade Francais: Mathis Ibo; Charles Laloi, Jeremy Ward (capt), Tani Vili, Lester Etien; Zack Henry, Paul Abadiel; Jack Iscaro, Alvaro Garcia Albo, Giorgi Melikidze; Pierre-Henri Azagoh, Jacques Botha; Juan-Martin Scelzo, Mathieu Hirigoyen, Yoan Tanga.
Replacements: Lucas Peyresblanques, Yanis Lux, Sergo Abramishvili, Setareki Turagacoke, Tanginoa Halaifonua, Thibaut Motassi, Louis Foursans-Bourdette, Samuel Ezeala.
Stuart Lancaster has made three changes to his Connacht side as they look to ensure passage to the last 16 of the Challenge Cup against Montauban.
Jack Carty (above) and Matthew Devine have returned from injury to form the half back partnership, while hooker Dave Heffernan is back to take his place between props Billy Bohan and Sam Illo.
The second row of Darragh Murray and Josh Murphy is retained, while captain Cian Prendergast, Jack Boyle and Sean Jansen complete the pack.
Harry West and Cathal Forde are the centres, flanked by Shane Jennings and Finn Treacy on the wings, with Sam Gilbert in the 15 jersey.
Connacht: Sam Gilbert; Shane Jennings, Harry West, Cathal Forde, Finn Treacy; Jack Carty, Matthew Devine; Billy Bohan, Dave Heffernan, Sam Illo; Darragh Murray, Josh Murphy; Cian Prendergast (capt), Paul Boyle, Sean Jansen.
Replacements: Dylan Tierney-Martin, Denis Buckley, Jack Aungier, Joe Joyce, Sean O'Brien, Ben Murphy, Sean Naughton, Sean Walsh.
Montauban: Jean Seux;; Gade Asaeli, Simon Renda, Maxime Mathy, Paul Vallee; Jerome Bosviel, Hugo Zabalza; Lucas Seyrolle, Maixent da Costa, Sione Mafileo; Clement Bitz; Lewis Bean, Fred Quercy (capt), Tjuee Uanivi, Nafi Ma'afu.
Replacements: Ru-Hann Greyling, Leo Aouf, Noa Kanika, Karl Wilkins, Mael Castel, Thomas Fortunel, Gibson Popoali'i, Facundo Pomponio.
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