There are four changes in the backs with Duncan Williams taking the place of Cathal Sheridan at scrum-half after the Sligo man broke a bone in his forearm last week with Ian Keatley remaining at out-half.
Johne Murphy and Gerhard van den Heever are both drafted into the side on the wings with Simon Zebo moving to full-back.
Denis Hurley comes in at first centre with Casey Laulala keeping his place at second centre.
Two of the four changes in the forwards involve the front-row with Irish international props Dave Kilcoyne and Stephen Archer joining hooker Duncan Casey who maintains his place to make his fifth start for the province.
O'Callaghan and Ryan make up the second-row and CJ Stander takes the place of Sean Dougall in the back-row with Tommy O'Donnell keeping his place and Coughlan captaining the side from no.8 once again.
Ger Slattery, James Cronin and BJ Botha provide the front-row cover with Dave Foley and Dougall ready to make an impact off the bench.
Gerry Hurley, JJ Hanrahan and Ronan O'Mahony are the three backs named in the replacements.
Munster face Scarlets at Parc y Scarlets on Saturday at 6:30pm. The game will be televised live on RTE and S4C.
Munster: Simon Zebo; Gerhard van den Heever, Casey Laulala, Denis Hurley, Johne Murphy; Ian Keatley, Duncan Williams; Dave Kilcoyne, Duncan Casey, Stephen Archer; Donncha O'Callaghan, Donnacha Ryan; CJ Stander, Tommy O'Donnell, James Coughlan(Capt). Replacements: Ger Slattery, James Cronin, BJ Botha, Dave Foley, Sean Dougall, Gerry Hurley, JJ Hanrahan, Ronan O'Mahony.
Contract Extension For Williams
Munster Rugby and the IRFU are pleased to announce that Duncan Williams has signed a one-year contract extension that will see him stay with the province until June 2015.
Williams, the most capped scrum-half in the squad, made his League debut against Connacht in December 2009 in Thomond Park and has made 63 appearances for the province.
The academy graduate moved on to a full contract at the start of the 2010/11 season and made his Heineken Cup debut against London Irish that October at the Madejski Stadium.
The 27-year-old has since made a steady progression increasing his game time each season, displaying invaluable experience in a key position.
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