"I felt good, but good isn't great and good isn't 100 percent," Moore said. "We're looking to be 100 percent. There are still a few things in doubt that we're not comfortable with. We're just going to give it a couple more days and see where we're at."
Since aggravating the muscle in a July 28 loss to the Yankees, Moore has maintained it only bothers him when throwing changeups.
The delay is not considered to be a setback in recovery.
"We're talking a very little bit, but enough to that we want to make sure it's not something I have to be shut down again for if I go back out there," Moore said. "It's kind of like picking a scab. It's great until I pick that scab once and then it turns into my arm not feeling 100 percent."
While he feels better, Moore does not have a target date for his return.
"The progress we have made is substantial. There's just a little more to go."
Sam Strong is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.