"Yeah, I'm good. You go through periods where you have a heavy workload and I just had a tired shoulder. Buck was trying to be more judicious with how he used me. Yeah, I just ended up not seeing a game in Kansas City."
O'Day, who pitched in 11 games in April, has thrown in just four so far in May. He was noticeably absent from the team's weekend series against the Royals and last pitched on May 8, in which he gave up a run in the O's win over the Nationals.
Without closer Zach Britton, who is on the disabled list, the O's have had to use O'Day and Brad Brach more than normal. The team is also operating with a six-man bullpen, making continuous roster moves to try to keep the relief corps fresh.
"Yeah, Zach's obviously out and we all have to step up and kind of carry that weight," O'Day said. "You'd like to have another late-inning arm. Zach was pretty good at pitching and we miss him, but that's no excuse. We just got to go out there when our name is called."
O'Day said the shoulder issue wasn't anything serious and said it's just part of the long season and unpredictable nature of being a reliever.
"Well, you could jump to the conclusion that I had a shoulder problem last year, but no, I think it's different," he said. "Less than a week ago I felt as good as I've felt in years. I feel fine."
Brittany Ghiroli has covered the Orioles for MLB.com since 2010. Read her blog, Britt's Bird Watch, follow her on Facebook and Twitter @britt_ghiroli, and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.