He will undergo an MRI on Saturday to figure out the severity of the injury.
Green, 25, was recently placed in the Yankees' starting rotation for the remainder of the season, but that is now in question. Bryan Mitchell, who has been out the entire season after fracturing his left foot in spring training, is a possibility. He threw 5 1/3 innings of one-run ball for Triple-A Scranton.
The Yankees just called up Luis Severino, but they had recently worked him as a reliever in the minors.
On Friday, the Orioles roughed up Green for four earned runs, including a long two-run homer from Pedro Alvarez, in Green's 1 2/3 innings. He said he felt pain in the right elbow and thought it would be smart to say something.
"Hopefully, it is nothing too serious," Green said.
Green entered the game at 2-3 with a 4.09 ERA. After the brief outing, his ERA shot up to 4.73.