Ireland head coach Andy Farrell has praised the "astonishing" progress made by back row Caelan Doris "as a leader and a professional" in recent years.

"We're excited to give him the reins and let's see what he can do with it," said Farrell before the Dublin game.

"To put him in that position is a massive privilege for me."

Defending Grand Slam champions Ireland have made six changes from the side that saw off France in their opening fixture in Paris for their encounter against an Italian side who lost by three points to England in Rome.

With O'Mahony missing with a calf complaint, Farrell had no reservations about handing the captain's armband to 25-year-old Leinster forward Doris given the impact he has had on and off the pitch.

"He's someone that has been on my mind for, certainly through the World Cup, and how he has come on as a leader and how he has dealt with being an international top class player," said the Ireland coach of Doris.

"Over the years, his story from his first cap to where he is now as a leader and a professional has been astonishing really behind the scenes.

"Obviously it's his first time captaining his country and he doesn't much of it for Leinster either.

"He's someone who is unbelievably professional, very diligent in his own preparation, so therefore because he's so comfortable in his own skin he's able to think out of the box as far as helping everyone else with the bigger picture stuff.

"Even the detailed stuff of his team-mates, and we've seen that flourish massively, over the last couple of years, but more so throughout the World Cup.

"He's very calm, calculated type of individual that will have that reassurance on the rest of the group."