Iain Henderson and John Cooney return for Ulster in Saturday's crucial Heineken Champions Cup tie against holders La Rochelle (5.30pm), but James Hume and Jacob Stockdale miss out.Henderson and Cooney come into the starting line-up after completing the return-to-play protocols that saw them miss the 39-0 drubbing by Sale Sharks in round one.Henderson captains Ulster from blindside flanker while Cooney resumes his half-back partnership with Billy Burns.Dan McFarland makes eight changes to the team that failed to register a point at the AJ Bell Stadium, with British and Irish Lions prop Rory Sutherland handed his first Ulster start after recovering from a knee injury.Tom Stewart and Marty Moore pack down alongside Sutherland while Sam Carter partners Alan O’Connor in the second row as Kieran Treadwell drops to the bench.Luke Marshall and Rob Lyttle replace the injured Hume and Stockdale at centre and wing respectively.Ulster said they are taking "every possible step" to ensure the game goes ahead as planned at Kingspan Stadium, where there are concerns the frozen pitch will not have thawed in time for kick-off.Ulster: Mike Lowry; Ethan McIlroy, Luke Marshall, Stuart McCloskey, Rob Lyttle; Billy Burns, John Cooney; Rory Sutherland, Tom Stewart, Marty Moore; Alan O’Connor, Sam Carter; Iain Henderson (capt), Nick Timoney, Duane Vermeulen.Replacements: Rob Herring, Eric O’Sullivan, Gareth Milasinovich, Kieran Treadwell, David McCann, Nathan Doak, Stewart Moore, Ben Moxham.Conor Murray starts for Munster on his return from injury as Graham Rowntree makes four changes for Sunday’s game against Northampton Saints (1pm).Murray, who has been sidelined for the past six weeks with a groin injury suffered on his 100th Ireland