Fit-again tight-head prop Furlong returns to replace Andrew Porter, with Ringrose coming in at centre for the injured Chris Farrell. The former England hooker has since revised that view and while more conservative options were available to Scotland's head coach, Townsend expressed confidence in the way the youngster has developed in the course of this season, saying he believes he has learned the error of his ways as a rugby player.
'It's a needs-must situation, but it's a situation where we've got a lot of trust and faith in Garry'.
Tadhg Furlong returns at tighthead as John Ryan drops out of the squad and Andrew Porter returns to the bench following two impressive performances by the 22-year-old understudy.
"He's trained really well over the last couple of weeks, but we just feel the balance of what we might expect from Ireland, along with the potential weather conditions, means having that extra full-back in the back three is better for us this week, but with Lee on the bench, we also know we've got an excellent winger to cover".
With Conan released to play for Leinster against Scarlets on Friday night, arguably paying for his over-eagerness in defence against Wales, Murphy is named as the replacement back rower. If he comes through unscathed he could come into the frame to face England on St Patrick's Day.
"I'll be watching how Seán leads the side".
Larmour has been preferred to Fergus McFadden on the bench.
Schmidt has shouldered that criticism since 2015.
Ringrose, who played every minute of last year's Six Nations, links up with Bundee Aki for the first time in what is the 25th different midfield partnership during Schmidt's time in charge.
"At this stage we have made the third most offloads. It's an area where people have loved to beat us with a stick, and it's probably overlooked by people that there is some continuity through our play".
IRELAND: R Kearney; K Earls, G Ringrose, B Aki, J Stockdale; J Sexton, C Murray; C Healy, R Best (capt), T Furlong; J Ryan, D Toner; P O'Mahony, D Leavy, CJ Stander. Iain Henderson, 20. Jordi Murphy, 21.