Retired NFL player Herschel Walker says he was dropped from speaking engagements because of his relationship with Donald Trump.

In an interview with TMZ Sports, the Heisman Trophy winner and former "Celebrity Apprentice" contestant said he's known Trump since "before he became 'The Donald.'"

"That's true, I've had a lot of people cancel speaking engagements with me because of [my relationship with Trump]," he told TMZ.

He added that Trump once told him "any publicity is good publicity" to which Walker responded, "It's good but not for me."

The 54-year-old said the presumptive Republican nominee is not racist.

Walker told TMZ Sports "Just because you build a wall, doesn't mean you're a racist."

Walker was referencing the sharp criticism Trump has faced for his statements on immigration and plan to build a wall along the U.S. border with Mexico.

The Associated Press contributed to this report.