
O’Sullivan said: “There were a couple of difficult calls to make.
“The front row was hard because Rory has played very well since recovering from injury, but Jackman pushed him close.
“We looked at Jamie Heaslip because of his form but on balance we decided to leave the back row as it is.
“Scrum-half was a tight call as well. It could have gone either way between Reddan and Stringer.”
Skipper Brian O’Driscoll and prop John Hayes will win their 80th caps at Croke Park on Saturday.
Ireland finished runners-up in last season’s RBS 6 Nations, winning their third Triple Crown in four seasons, but crashed out of the World Cup at the group stage.
Ireland team for the RBS 6 Nations match against Italy at Croke Park on Saturday:
G Dempsey (Leinster); A Trimble (Ulster), O’Driscoll (Leinster, captain), G D’Arcy (Leinster), G Murphy (Leicester); R O’Gara (Munster), E Reddan (Wasps); M Horan (Munster), R Best (Ulster), J Hayes (Munster), D O’Callaghan (Munster), M O’Kelly (Leinster), S Easterby (Llanelli), D Wallace (Munster), D Leamy (Munster).
Replacements: B Jackman (Leinster), T Buckley (Munster), M O’Driscoll (Munster), J Heaslip (Leinster), P Stringer (Munster), P Wallace (Ulster), R Kearney (Leinster).