Tillman said the tests are precautionary and added he wasn't worried that the injury would keep him out of the team's starting rotation.
"I personally don't," Tillman said. "We did a couple tests with the trainers and they said it looked really good. … It's just kind of a 'just-in-case' thing."
Tillman said he began to feel discomfort warming up before Sunday's start and the tightness continued throughout his three innings of work before he was pulled.
"I wouldn't say it's a pain," Tillman said. "It's more dead. It just feels achey and dead. I've dealt with it before in bullpens and you kind of manage it and kind of get your work in. But during a start, you've got to go out there and give it your best. It's one of those things where you don't want to make it worse. I'll go get it checked out just in case."
The 24-year-old Tillman left the game trailing 2-0 after allowing a two-run homer to
"It started barking on me a little bit and I felt OK, but at the same time you don't want to push anything and make it worse," Tillman said. "I'd like to keep going, but at the same time, the team doesn't deserve someone out there that's not going to be able to throw 100 percent."