Johnny Sexton will captain Ireland for the first time in Thursday's clash with Russia as Joe Schmidt's men bid to set their World Cup back on track.
Fly-half Sexton had declared himself fit and ready to fire back into action on Sunday, the day after missing Ireland's 19-12 loss to hosts Japan.
The British and Irish Lions playmaker missed the Shizuoka defeat by the Brave Blossoms due to the thigh bang he had sustained in the 27-3 bonus-point win over Scotland.
But now the 34-year-old is not just ready to return, he has been pitched in from the off and as skipper to take on Russia - indicating the importance boss Schmidt has placed on Ireland firing an immediate riposte after that shock Japan loss.
Head coach Schmidt has made 11 personnel changes from the Japan defeat to take on Russia in Kobe, to account for the five-day turnaround.
Garry Ringrose and Peter O'Mahony are the two Ireland players who will start three games in 11 days, as the reality of the tournament's dense schedule catches hold.
Leinster star Ringrose will pair up with the returning Bundee Aki in midfield.
Chris Farrell has been ruled out of the Russia game due to a concussion, with Robbie Henshaw still working back from hamstring trouble.
While O'Mahony will start his third game in a row, the British and Irish Lions back-row forward only lasted 25 minutes of the win over Scotland before failing a head injury check.
The Munster stalwart, who passed the initial head injury tests, did not have to complete the return-to-play protocols and duly faced Japan.
And now he will push straight back into action, with Ireland eyeing victories over Russia and Samoa to complete their Pool A schedule and qualify for the quarter-finals.
Ireland will field an all-Munster front-five to take on the Russians, with Tadhg Beirne and Jean Kleyn pairing up at lock.
Jordi Murphy is handed an immediate start at number eight having replaced the injured Jack Conan in the 31-man squad.
Fly-half Joey Carbery will cover scrum-half from the bench, indicating the Munster star's versatility in the Ireland ranks.
— Irish Rugby (@IrishRugby) October 1, 2019
Ireland team to play Russia
Forwards: 1 Dave Kilcoyne (Munster), 2 Niall Scannell (Munster), 3 John Ryan (Munster), 4 Tadhg Beirne (Munster), 5 Jean Kleyn (Munster), 6 Rhys Ruddock (Leinster), 7 Peter O'Mahony (Munster), 8 Jordi Murphy (Ulster)
Backs: 9 Luke McGrath (Leinster), 10 Jonathan Sexton (CAPTAIN, Leinster), 11 Keith Earls (Munster), 12 Bundee Aki (Connacht), 13 Garry Ringrose (Leinster), 14 Andrew Conway (Munster), 15 Rob Kearney (Leinster)
Replacements: 16 Sean Cronin (Leinster), 17 Andrew Porter (Leinster), 18 Tadhg Furlong (Leinster), 19 Iain Henderson (Ulster), 20 CJ Stander (Munster), 21 Joey Carbery (Munster), 22 Jack Carty (Connacht), 23 Jordan Larmour (Leinster)