Stewart given first Ireland start amid injury worries at hooker
Sheehan hobbled off with a foot injury in last weekend's 29-10 win over England, while Leinster teammate Kelleher has not featured in any of Ireland's warm-up games due to a hamstring problem.
Stewart made his Irish debut off the bench against Italy earlier this month after a breakthrough season for Ulster where he finished as the United Rugby Championship's top try scorer with 16 in 15 games, a remarkable feat for a hooker.
Very much in the all-action, try-scoring mould of Sheehan, Stewart went over eight times in his final four matches - including back-to-back hat tricks.
He starts ahead of experienced Ulster teammate Rob Herring in Bayonne, France on Saturday.
There are first warm-up starts for Conor Murray, Cian Healy and Finlay Bealham - each of whom looks certain to be included in Farrell's final 33-man squad.
Healy will become the outright third-most-capped Irish player with his 125th appearance.
While Ryan Baird gets another chance to show his versatility in the back row, the exclusion of Jacob Stockdale and Ciaran Frawley from the matchday 22 would appear to lengthen their odds of making it on the plane to France.
Ireland team:
15. Jimmy O'Brien, 14. Mack Hansen, 13. Robbie Henshaw, 12. Stuart McCloskey, 11. Keith Earls, 10. Jack Crowley, 9. Conor Murray; 1. Cian Healy, 2. Tom Stewart, 3. Finlay Bealham, 4. Iain Henderson (captain), 5. Tadhg Beirne, 6. Ryan Baird, 7. Josh van der Flier, 8. Caelan Doris
Replacements: 16. Rob Herring, 17. Jeremy Loughman, 18. Tom O'Toole, 19. James Ryan, 20. Peter O'Mahony, 21. Craig Casey, 22. Ross Byrne, 23. Garry Ringrose.
