The brothers are set to meet in the centres on Saturday after the Brumbies rookie passed concussion tests and was named at No.13.
Wallabies star Rob Valetini will be rested though, while the Reds have also put in-form winger Tim Ryan on ice and will be without injured Test duo Hunter Paisami (ankle) and Matt Faessler (knee).
Paisami's absence allows Isaac Henry a chance in the No.12, with 18-year-old Pritchard to provide bench cover on debut after an eye-catching pre-season and dominating at junior level.
Reds playmaker Tom Lynagh, who has been rebuilding strength in his injured upper-leg, will miss another week after coach Les Kiss had teased at a possible return for the Wallabies' flyhalf.
Carter Gordon will wear the No.10 after an encouraging display in his Reds debut last week, while Harry McLaughlin-Phillips is on the bench.
Former Reds backrower Tuaina Taii Tualima will replace Valetini while the Brumbies' Test lock Nick Frost will make his return in a curtain-raiser earlier on Saturday.
Andrew Kellaway will play his first game of the season on Friday for the NSW Waratahs, selected at fullback to face the Hurricanes in Sydney.
Test hooker Folau Faingaa has also recovered from a concussion to earn his first start for the Waratahs, while Triston Reilly will take Harry Potter's (toe) place on the wing.
Kellaway had been unseated by club rugby bolter James Hendren in back-to-back wins to start the season before last weekend's bye.
"Kells (Andrew Kellaway) has worked really hard in training and has earned his place. He brings experience, he is fresh and he is ready," coach Dan McKellar said.
The Western Force, fresh off a drought-breaking defeat of Moana Pasifika in New Zealand last Friday, will be bolstered by the return of Wallabies Nick Champion de Crespigny and Brandon Paenga-Amosa for Saturday's clash with the Highlanders in Dunedin.
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