For about two weeks, Ludwick has been hitting, and he began taking batting practice on the field with the team Thursday.
"I feel good," Ludwick said before Sunday's finale vs. the Pirates. "I've had some sore days, but nothing that hasn't gotten better within a day or two. I'd say I'm getting more sore if areas other than my shoulder -- my back and my legs and wrist. It's going to a process. It's obviously going to be a longer rehab assignment. We'll see how he plays out."
The Reds have missed Ludwick's run production from the right side of the plate this season. In 2012, he batted .275 with 26 home runs and 80 RBIs, which earned the free agent a two-year, $15 million contract to return to Cincinnati.
"He's worked hard, really hard," manager Dusty Baker said. "I'm proud of how he's worked. The average person would have gotten frustrated by now. I talked to him. He said, 'Man, there's a lot of RBIs out there.' "
The Dragons will be playing at Lansing when Ludwick joins them this week. Usually, veterans go to rehab assignments where affiliates are playing home games, but Triple-A Louisville, Double-A Pensacola and Dayton are all on the road.
Ludwick can be on a rehab assignment for up to 20 days. He hopes he will not need all of them.
"But I'm not in charge, either," Ludwick said. "I let those guys make the decisions, and I play."
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, and follow him on Twitter @m_sheldon. This story was not subject to the approval of Major League Baseball or its clubs.