The Rangers placed Pruitt on the 15-day injured list Wednesday with a right meniscus injury, Evan Grant of The Dallas Morning News reports.
The Rangers selected Pruitt's contract from Triple-A Round Rock on Saturday, Jeff Wilson of RangersToday.com reports.
Pruitt signed a minor-league contract with the Rangers on Wednesday that includes an invitation to spring training, Evan Grant of The Dallas Morning News reports.
Oakland outrighted Pruitt (forearm) to Triple-A Las Vegas on Wednesday.
Pruitt (forearm) is scheduled to throw live batting practice against JJ Bleday (knee) on Friday, the team's official site reports.
The Athletics placed Pruitt on the 15-day injured list Sunday with a right forearm strain.
Pruitt did not factor into the decision Wednesday, allowing one walk over two scoreless innings in a 2-0 victory over the Rangers. He struck out two.
Pruitt (2-6) got the win against the Astros on Saturday, firing a scoreless two-thirds of an inning.
Pruitt will serve as Oakland's opening pitcher in Saturday's game agains the Twins.
Pruitt (1-6) took the loss against the Red Sox on Saturday, allowing four earned runs on four hits over 1.2 innings. He didn't walk a batter or record a strikeout.