Robbie Henshaw will partner Bundee Aki at centre for his first taste of the World Cup in Japan in Ireland's Pool A decider against Samoa on Saturday.
The British and Irish Lions powerhouse has missed all three of Ireland's World Cup matches so far, having picked up a hamstring injury in training just days after landing in Japan.
But now the 26-year-old is fit and ready to fire into a match Ireland must win with a bonus point to guarantee their place in the quarter-finals.
Ireland have rolled out the bulk of their big guns to take on the physical and attacking Samoans, though Jordan Larmour has slotted in at full-back in place of Rob Kearney.
Tadhg Beirne replaces his Munster colleague Peter O'Mahony at blindside flanker, with boss Joe Schmidt keen to ease the workload on the British and Irish Lions back-rower.
Johnny Sexton starts at fly-half while Joey Carbery takes a seat on the bench, with Ireland buoyed to have both play-makers back to full fitness.
Ireland: 15 Jordan Larmour, 14 Keith Earls, 13 Robbie Henshaw,12 Bundee Aki, 11 Jacob Stockdale, 10 Jonathan Sexton, 9 Conor Murray; 1 Cian Healy, 2 Rory Best (c), 3 Tadhg Furlong, 4 Iain Henderson, 5 James Ryan, 6 Tadhg Beirne, 7 Josh van der Flier, 8 CJ Stander.
Replacements: 16 Niall Scannell, 17 Dave Kilcoyne, 18 Andrew Porter, 19 Jean Kleyn, 20 Peter O'Mahony, 21 Luke McGrath, 22 Joey Carbery, 23 Andrew Conway.