The 21-year-old all-star was injured Monday in a game against the Tampa Bay Rays when he rounded first base on an infield single and hit the bag awkwardly, causing his knee to buckle inward.
Machado was carted off the field with what seemed to be a very serious injury, but was diagnosed only with a torn medial patellofemoral ligament.
Such injuries require up to two months to heal, and the Orioles said Machado could possibly be back to running as early as six weeks.
Machado, who was hitting .283 with an American League-leading 51 doubles, had played in 207 consecutive games since his major league debut last year, including 156 this season.
2014: The Year in Music [PHOTOS]