Machado fell to the ground after taking an awkward swing during Monday's game against the New York Yankees. He was helped off the field.
An MRI on Tuesday revealed no structural damage.
It will be Machado's second stint on the DL. He started the season there while recovering from offseason surgery on his left knee.
The move was retroactive to Aug. 12, and the Orioles called up infielder Cord Phelps from Triple-A Norfolk. To make room on the 40-man roster, catcher Matt Wieters, who had Tommy John surgery on June 17, was transferred to the 60-day DL.
The 22-year-old Machado has a .278 batting average with 12 home runs and 32 RBIs in 82 games this season.
Chris Davis started at third base for the Orioles on Wednesday. He replaced Machado on Monday and has 74 games of major league experience at the position.
Phelps was batting .258 with 49 RBIs at Norfolk.
The Associated Press contributed to this report.
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