"I'm pretty much doing everything," he said before he got the news.
Kratz, who remains fourth on the team with eight homers, has been hitting, catching and running. He said he feels better than he felt before he injured himself last month running to first base in Milwaukee.
"I'm very surprised," Kratz said. "It's amazing. I know I'm supposed to take my time, but I've passed every test. Eventually, you'll have to play in a game. I feel really close to that."
Left-hander Jeremy Horst, who has been on the DL since June 16 with a sprained left elbow, will continue his rehab with Lehigh Valley. He made his first rehab appearance Saturday with Class A Clearwater.
Todd Zolecki is a reporter for MLB.com. Stephen Pianovich is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.