Dirks, out since March following back surgery, was recalled from his rehab assignment Wednesday but kept on the 60-day disabled list, a move that raised concerns he had suffered a setback. Rand wouldn't characterize it as a setback, but said they're going to be cautious with the injury to avoid risking something worse.
"Basically, he got muscular soreness and tightness right in and around the surgical site. Not unusual," Rand said. "Basically, it's just due to the increase in activity. No matter what you do with batting practice, even simulated games can't duplicate game action as far as the intensity that guys put forth."
The decision to pull him off of rehab, Rand said, was as much a clerical decision as it was a physical one.
"If it wasn't for the fact that he's missed so much time and this is his Spring Training, like a normal rehab assignment, you'd probably say give it a couple days," Rand said. "But in his case, every day's very, very important for him, because he doesn't get that many of them, and we want to make sure we get every one we can."
By rule, position players can spend up to 20 days on a rehab assignment before teams have to decide the next step: Call up the player, keep him on the DL without rehab, or option him to the Minor Leagues.
Dirks spent eight days on rehab before being recalled. He'll have 12 days left once his rehab assignment resumes.
Jason Beck is a reporter for MLB.com. Read Beck's Blog and follow him on Twitter @beckjason. Matt Slovin is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.