ESPN said Wednesday, "We are addressing it" and would not go into further details.
The former all-star pitcher made the controversial comments Tuesday with Sports KCSP 610 AM in Kansas City, Missouri.
Schilling, who has been known for his outspoken political comments, was asked if Clinton should go to prison for accusations that she put classified State Department emails on a private server.
"I hope she does. If I'm going to believe, and I don't have any reason not to believe, that she gave classified information on hundreds if not thousands of emails on a public server after what happened to General Petraeus, she should buried under a jail somewhere," Schilling said.
CNN Money reports then asked about the possibility of Clinton vs. Donald Trump in the general election, Schilling responded, "If she's allowed to get to the general election before she's in prison, I'll be stunned and I'll be upset."