Tony Cingrani may miss at least part of the Reds upcoming road trip to Milwaukee, Houston and Chicago to get therapy on his back.
Cingrani left the game Tuesday in the second inning.
Baker would like him to join the team even if he is not ready to pitch.
"I like the guys to stay with us so they can experience the pennant race," Baker said.
The Reds are researching the root cause of the injury.
"We are still learning about him," Baker said. "You don't know what it comes from. He could have been in a traffic accident when he was 10 years old, or hutt it playing basketball.. We will have to come up with a regimen that keeps it from recurring."