Kearns started rehab stint.

[Kirkendall]

Austin Kearns began a rehabilitation assignment with Triple-A Louisville Wednesday.

Kearns, who has been on the disabled list with a sore thumb, went 2-for-3 with a double. No matter how well he hits, he won't join the Reds until June 22 when they open a three-game series in New York against the Mets.

"We've told Austin he'll be with the Louisville club through Monday," Reds general manager Dan O'Brien said. "The only asterisk would be if Austin tells us he's not ready."

That's not likely. Kearns wasn't happy when his previous rehab assignment lasted eight games. Kearns was coming back from a broken left forearm that time.

In that case, he was taking batting practice and working out well before he was eligible.

This time, the thumb injury, which was the result of an open sore, kept him from swinging a bat until three days ago.

Kearns is one of three Reds on the DL. Juan Castro was eligible to return Wednesday. Aaron Harang, like Kearns, was eligible to come off today.

Harang, who has a sore tendon in his elbow, will make a rehab start Friday for Louisville.

"If all goes well, he'll meet us in St. Louis and throw a side on Sunday," Manager Dave Miley said.

Harang probably will be back in the rotation after the rehab start.

"It will be up to Miles and (pitching coach) Don Gullett to slot him into the rotation at that point," O'Brien said.

Harang doesn't anticipate a problem.

"I've had no pain, no problems," he said.

Castro, out with a strained rib cage muscle, went through a pretty strenuous session Wednesday.

The Reds will wait to see how Castro feels today before deciding on a rehab assignment for him.