CHICAGO (AP) — Baltimore third baseman Manny Machado will have season-ending surgery on his ailing right knee.

Dan Duquette, the vice president of baseball operations for the Orioles, says Machado told the team on Friday that his knee wasn't responding to rest. Duquette says Machado conferred with his doctors and felt surgery was the best option.

Machado had a similar injury to the other knee last year, when he missed the final week of the season. He then had surgery and didn't play in a regular-season game this year until May 1.

It's a difficult blow for the AL East-leading Orioles, who are going for their first division title since 1997. They had an eight-game lead over the New York Yankees heading into Saturday's action.