In June, basketball legend Shaquille O'Neal announced he was joining Papa John's board of directors and investing in nine Atlanta-based locations. The move came just over a year after the company's founder, John Schnatter, resigned as chairman for using a racial slur during a conference call. O'Neal has also replaced Schnatter in the brand's ads.

"We came in when [Schnatter] made the big mistake," O'Neal tells CNBC Make It on Monday night at Sports Illustrated's Sportsperson of the Year award event in New York City.

Ever since, Schnatter — who started the pizza brand in a broom closet in his father's tavern in 1984 and helped it grow to nearly 3,000 restaurants in 49 states and 20 international markets — has been making headlines for controversial statements regarding the company.

In October, Schnatter told FOX Business that no one on the board knows anything about pizza, and franchises are under "a lot of duress" because the unit economics are not healthy. (After Schnatter's departure, Papa John's International stock has surged nearly 50% so far this year, and Schnatter is still the largest individual shareholder.)

What's more, in November, Schnatter told Fox affiliate WDRB in Louisville, Kentucky, that he believes the company's new management has changed his famous pizza recipe.

"I've had over 40 pizzas in the last 30 days, and it's not the same pizza, it's not the same product," Schnatter told WDRB.

Both O'Neal and Papa John's CEO Rob Lynch deny the recipe has changed.

"Never. There is no change," O'Neal says. "Sometimes people don't know when to keep their mouths shut," he added in response to Schnatter's series of accusations.

"I'm not going to go back and forth with this guy. It doesn't matter what he has said about me. I don't care. I'm on a mission to make [Papa John's] the No. 1 brand."

According to O'Neal, his fellow board members are also unfazed by Schnatter's comments to the media.

"We don't worry about him. He has bigger problems" he needs to handle, says O'Neal.

On Thursday, Dec. 7, Schnatter filed a lawsuit against an advertising firm alleging it leaked an unauthorized recording of the infamous conference call that lead to his ousting. On the same day, his wife of 32 years filed for divorce, calling the couple's marriage "irretrievably broken."

In a statement to CNBC Make It on Tuesday, Dec. 10, Schnatter says while he has nothing but nice things to say about Shaq, the company's current leadership "is just not leveraging his value to the benefit of the franchisees" and a majority are losing money as a result.

"Under my leadership, I always put the quality of the pizzas, the loyalty to customers, and my affection for the employees first at Papa John's. It's all too obvious now, though, that the company is ignoring the success of the past and placing the stock price ahead of both the people and the products."

In June, O'Neal said in a statement that he's "thrilled" to be involved with Papa John's as he has been eating the pizza since his early days playing basketball at Louisiana State University.

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