Papa John's Pizza says the NFL is the cause of its sales slump.

John Schnatter, founder and CEO of Papa John's, called out NFL leadership during an earnings call Wednesday morning, saying the league's national anthem player protests have "hurt" his company, according to CNBC.

"The NFL has been a long and valued partner over the years, but we are certainly disappointed that NFL and its leadership did not resolve the ongoing situation to the satisfaction of all parties," Schnatter said Wednesday. "This should have been nipped in the bud a year and a half ago."

Schnatter says declining NFL viewership and negative consumer sentiment have caused lower third quarter sales.

Papa John's announced same-store sales grew 1 percent in the third quarter, short of an expected 1.4 percent rise.

Shares of Papa John's fell more than 11 percent Wednesday morning and Schnatter personally lost more than $70 million of his net worth, according to Forbes.

Papa John's has been the official pizza sponsor of the NFL since 2010.