Garry Ringrose will solve Ireland's midfield problem by starting at outside centre in Saturday's Six Nations clash with Scotland in Dublin.
The 23-year-old has finally shaken off ankle trouble suffered in January, and slots into midfield to ease the loss of long-term injured trio Jared Payne, Robbie Henshaw and Chris Farrell.
Ulster centre Payne has not played since last summer's Lions tour to New Zealand, having suffered persistent headaches.
Leinster star Henshaw dislocated his right shoulder in Ireland's 56-19 win over Italy in Dublin, and Munster's Farrell tore knee ligaments in training.
Quick-witted 23-year-old Ringrose therefore becomes the third man to wear Ireland's 13 shirt in this year's Six Nations.
British and Irish Lions duo Tadhg Furlong and Iain Henderson return after hamstring problems - though Henderson only to the bench, with youngster James Ryan partnering Devin Toner at lock.
Henderson had been widely tipped to slot straight back into the starting line-up, but coach Joe Schmidt has kept faith with his most-selected player in Toner.
The 31-year-old will this weekend make his 44th Ireland start under Schmidt, in the Kiwi coach's 54th match at the helm.
Pivotal half-backs Conor Murray and Johnny Sexton have also shrugged off knocks in time for Saturday's Aviva Stadium showdown, as Ireland hunt a fourth-straight win in this year's competition.
Beat Scotland this weekend and Ireland would then face England at Twickenham on Saturday, March 17, chasing a first Grand Slam in nine years.
Schmidt conceded Ringrose's selection after just an hour of club rugby with Leinster since January was "needs-must" given Ireland's injury problems.
"There's always concerns about players for different reasons, and Garry's only had six games in this entire season," said Schmidt.
"That's something you calculate in but sometimes you don't have the luxury of a plethora of options.
"Garry's been extraordinary when he has played for us, he's done great.
"We're hoping he can hit the ground running and get straight back into that form.
"He's a smart player, and hopefully he can get the balance between when he has to work hard and when he can get a breather back on the pitch.
"It's a needs-must situation, but it's a situation where we've got a lot of trust and faith in Garry."
— Irish Rugby (@IrishRugby) March 8, 2018
Ireland team to play Scotland
FORWARDS: 1 Cian Healy (Leinster), 2 Rory Best (CAPTAIN, Ulster), 3 Tadhg Furlong (Leinster), 4 James Ryan (Leinster), 5 Devin Toner (Leinster), 6 Peter O'Mahony (Munster), 7 Dan Leavy (Leinster), 8 CJ Stander (Munster)
BACKS: 9 Conor Murray (Munster), 10 Johnny Sexton (Leinster), 11 Jacob Stockdale (Ulster), 12 Bundee Aki (Connacht), 13 Garry Ringrose (Leinster), 14 Keith Earls (Munster), 15 Rob Kearney (Leinster)
REPLACEMENTS: 16 Sean Cronin (Leinster), 17 Jack McGrath (Leinster), 18 Andrew Porter (Leinster), 19 Iain Henderson (Ulster), 20 Jordi Murphy (Leinster), 21 Kieran Marmion (Connacht), 22 Joey Carbery (Leinster), 23 Jordan Larmour (Leinster)