The Leinster captain has recovered from a damaged transverse process sustained in their win over France last month to take his place at number eight back from club team-mate Jordi Murphy for their crunch RBS 6 Nations match against Wales in Cardiff on Saturday.
There are no surprises from Ireland head coach Joe Schmidt after his side comprehensively defeated England 19-9 in Dublin 11 days ago, with his side knowing that a win would leave them with an 80-minute showdown against Scotland in Edinburgh next week to give them the perfect start to a Rugby World Cup year.
With Heaslip making a swift return to the pack after sitting out the win over England, Murphy must make do with a place on the bench at the expense of Tommy O’Donnell.
The good news for Ireland fans is that talisman outside-half Johnny Sexton starts, despite limping off against England with hamstring troubles, while centre Jared Payne and flanker Sean O’Brien came through graduated return-to-play protocols after being concussed against England.
If the lure of retaining their title and going one better with a Grand Slam isn’t enough of an incentive for the green machine, they are also chasing an Irish record 11th successive win, and have an impressive winning record in the Welsh capital.
There will be added emotion for their captain and talisman Paul O’Connell, who will win his 100th Ireland cap on his 50th Six Nations appearance, Sexton will win his 50th cap, while Leinster loosehead prop Cian Healy will win his 50th cap when he comes off the bench.
Ireland: Rob Kearney (Leinster); Tommy Bowe (Ulster), Jared Payne (Ulster), Robbie Henshaw (Connacht), Simon Zebo (Munster); Johnny Sexton (Racing Metro), Conor Murray (Munster); Jack McGrath (Leinster), Rory Best (Ulster), Mike Ross (Leinster), Devin Toner (Leinster), Paul O’Connell (Munster, captain), Peter O’Mahony (Munster), Sean O’Brien (Leinster), Jamie Heaslip (Leinster).
Replacements: Sean Cronin (Leinster), Cian Healy (Leinster), Martin Moore (Leinster), Iain Henderson (Ulster), Jordi Murphy (Leinster); Eoin Reddan (Leinster), Ian Madigan (Leinster), Felix Jones (Munster).
MORE: The latest football news
MORE: The latest tennis news
BIOGRAPHY: Anthony Martial