CLEVELAND -- Detroit Tigers pitching coach Chris Bosio will be away from the team for at least two weeks after doctors advised him to get rest due to an undisclosed medical issue, manager Ron Gardenhire said.

Bosio started feeling unwell on Monday night and underwent testing on Tuesday, Gardenhire said. He has declined to be more specific than that.

"The doctors just want him to sit back and relax a little bit here. That's about all we can say," Gardenhire said. "As far as health goes, he's fine. He's been through a little bit of a health issue, and everything's taken care of and he's on the mend. That's all we can say.

"He's irritated like (heck) and wants to be with this baseball team, but he's going to do what's right."

Gardenhire said Bosio would still assist with video scouting of opponents and could communicate with pitchers by call and text as needed.

Bullpen coach Rick Anderson has served as acting pitching coach since Tuesday and will continue in that role in Bosio's absence.

Tigers roving minor-league pitching instructor A.J. Sager has served as bullpen coach but it's unclear if he'll continue in that role beyond this series.

"There are decisions to be made there, because he's also very important to our minor league organization," Gardenhire said. " I think he would be fine here, but he has other duties that are pretty important, running our whole pitching operation in the minor leagues. You hate to take a guy away for a couple weeks."

Bosio was hired by the Tigers this winter after spending six seasons as pitching coach for the Chicago Cubs.