The 24-year-old joins Nathan White, Ultan Dillane and Kieran Marmion on the bench, and Robbie Henshaw starts at inside centre.
Bealham qualifies for Ireland through his grandparents having been born in Australia, and has played four times for Ireland U20s and twice for the Emerging Ireland side, as well as in all of Connacht's GUINNESS PRO12 this season.
"He's slotted in really well," said Ireland assistant coach Simon Easterly. "He's been involved with the squad from the very start. This is his first opportunity to get a taste of Test match rugby.
"He's another product of Connacht going really well this year, in the GUINNESS PRO12 in particular, and they're still in the European quarter-finals.
"He's done really well, come in and impressed everyone. He's done his hard work, got stuck into his job.
"Now he's got an opportunity to show what can do at the highest level and I'm sure he'll be well-equipped for that."
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