His Cork Constitution club-mate Tom Gleeson returns to the squad after featuring for the Northern Hemisphere side in the Heroes Rugby Challenge last Saturday at Twickenham.
Meanwhile, Munster stalwart Ronan O'Gara is set to achieve another milestone in Llanelli this weekend when he plays his 100th match in the Heineken Cup.
"I was honoured to present John Hayes with his cap for reaching 100 Heineken Cup matches last month. He was the most fitting Munster man to achieve that milestone," admitted O'Gara, who was in match-winning form in the victories over Northampton Saints and Castres Olympique.
"It is a competition that has given me every possible emotion - and that's why you play the game. I have had wonderful moments and disappointing moments, but that's why you get involved in sport.
"And that's why this team is so special to me and why the fans are so loyal to the Heineken Cup - it is a wonderful ambassador for northern Hemisphere rugby."
MUNSTER Squad (v Scarlets) - Backs (12): Conor Murray, Tomas O'Leary, Ronan O'Gara, Ian Keatley, Scott Deasy, Tom Gleeson, Danny Barnes, Will Chambers, Simon Zebo, Lifeimi Mafi, Denis Hurley, Johne Murphy,
Forwards (18): Marcus Horan, Wian du Preez, Stephen Archer, BJ Botha, John Hayes, Damien Varley, Denis Fogarty, Donncha O'Callaghan, Donnacha Ryan, Mick O'Driscoll, Ian Nagle, Paul O'Connell, Billy Holland, Peter O'Mahony, Niall Ronan, Tommy O'Donnell, Denis Leamy, James Coughlan.