Matt Harrison has been shut down from baseball activities after experiencing lower back stiffness on his right side.

Harrison is scheduled to have an MRI exam Thursday. He will then return to the Dallas-Fort Worth area for further evaluation on Monday by Dr. Drew Dossett, who performed both of his back surgeries for a herniated disk last April and May.

Harrison began his throwing program earlier than expected this off-season and didn’t encounter any setbacks, reporting to Texas Rangers’ spring training ready to win his spot back in the rotation.

That still could happen, but this is not a good sign.

“Not a big alarm, but a little bit concerned,” Harrison said. “I just hope that it’s not a serious issue and something I can take a few days down and stay on top of my core program and get right back out there. Hopefully that’s the case, but it’s not fair to say that I’m not worried about it, because I’ve had a lot of issues recently.”

Rangers general manager Jon Daniels and manager Ron Washington are hoping for the best.

“Hopefully this is irritation involved with getting going and he can push through it,” Daniels said. “After what he went through last year and the two surgeries, I feel for him.”

Said Washington: “No reasons to have concerns yet. We’ll just wait-and-see how it plays out.”

Harrison, 28, made only two starts last season before undergoing two back surgeries in April and May to fix a herniated disk. He had a third surgery later in the season for thoracic outlet syndrome. He dealt with neck stiffness a few days ago, but believed that is unrelated to the lower back issues he is now experiencing.