Carter's bat broke in the seventh inning on a 3-1 fastball from Kansas City's Matt Strahm, which he hit to second baseman Whit Merrifield for a groundout. A piece of the bat hit the boy, who was sitting about seven rows behind the third-base dugout.
"You never want to have something like that happen to a kid or anyone in general," Carter told The Associated Press. "I guess the good side of it is the square part of the bat didn't pierce him or anything like that. So, I hope he's OK."
Carter told the AP he will try to speak with the family.
"Once I figure out what happened to the kid, where they're at, hopefully, I can get a hold of him," he said. "Hopefully, it's not too bad."
Bryan Hoch is a reporter for MLB.com. Follow him on Twitter @bryanhoch and read his MLBlog, Bombers Beat. This story was not subject to the approval of Major League Baseball or its clubs.