Cowser, 23, has hit .330 with 10 home runs and 40 RBIs for Triple-A Norfolk this year. He was the fifth pick in the 2021 draft.
Even after losing six of their past seven games, the Orioles are in position for the top wild card in the American League, and their farm system has remained loaded with hitting prospects.
Late last month, they called up infielder Jordan Westburg, the No. 32-ranked prospect by MLB Pipeline. Cowser is No. 14 on that list, and Baltimore also has the No. 1 prospect in Class A shortstop Jackson Holliday.
The Orioles selected the contracts of Cowser and right-hander Eduard Bazardo from Norfolk and optioned outfielder Ryan McKenna to Norfolk. They also designated catcher Anthony Bemboom and right-hander Chris Vallimont for assignment before Wednesday night’s game at Yankee Stadium.