The two signs were hanging on the front fence of the league's baseball field. Maintenance crews noticed they were missing when they came to mow the grass.
"I was more disheartened. These are just little kids out here, and it's for them," Mitchener told WXIN. "It makes me wonder why someone would want to do that. I can't understand. It was more disappointment than anger."
This is the inaugural season for Marion's Babe Ruth Baseball League, and more than 260 players between the ages of 4 and 14 participate, the television station reported.
The signs are not worth much to thieves, but the league will have to pay for new signs, Mitchener told WXIN.
“Every dollar does count. We don’t have an entity where we generate money from, all of our money comes from donations and registration from kids," Mitchener told the television station. "So yes, it hurts but we will definitely replace them. It’s part of who we are."
Mitchener said league officials are discussing the idea of adding security cameras on the grounds, according to WXIN. There are already security alarms on the buildings