"I'm concerned whenever a guy takes five or six days off from throwing," Leyland said Wednesday morning. "It has gotten to the point where I'm concerned."
Rodney's throwing is on hold until at least next week after he had more soreness while throwing. An MRI exam on his shoulder revealed no structural damage, and his injury is officially listed as tendinitis.
"Nothing bad," Rodney said. "Just a little inflammation. Take a week's rest."
The pain, Rodney said, only surfaces when he throws from a distance. He feels fine playing catch from 60 feet, but said he feels the discomfort when he stretches out to 90 feet.
That said, Leyland cautioned, the Tigers' medical staff expects Rodney to be fine with rest and medicine. To him, it's not a story yet.
"But to say I'm not concerned, I'd be lying," Leyland said, "and I'm not going to do that."
Part of the concern regarding Rodney, of course, is the role that he holds. With fellow right-hander Joel Zumaya expected out until at least the season's second half following reconstructive surgery on his shoulder last fall, Rodney is Detroit's primary setup man.
Part of the Tigers' priority in this camp has been to identify a reliever who can set up ahead of Rodney in the seventh inning and pitch the eighth on occasion when Rodney has a day off. If Rodney isn't ready to open the season, they could be looking for two such pitchers.
The other cause for concern is Rodney's history. Tendinitis was among the injuries he battled early last season, when he had two different stints on the disabled list. He wasn't completely healthy until he came off the DL again in early August. When he did return, however, he was borderline dominant, posting a 2.82 ERA with 29 strikeouts over 22 1/3 innings and a .208 batting average allowed.
When he's healthy, history shows he's an effective late-inning pitcher. It's getting him there that can be a challenge.
"He has plenty of time right now," Leyland said. "But if we're sitting here 10 days from now, two weeks from here saying the same thing, then we've got issues."
Jason Beck is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.