The article uses four Twitter statements from fans to support the allegation. One of them directly mentions ESPN but does not state specifically what was heard on the audio.

The Daily News has clarified its reporting to state the slurs were picked up on crowd mics, not ESPN, and also later updated its story by saying, "Although Twitter has been abuzz with angry backlash, no available audio has surfaced to confirm the social media accusations."

The Post-Dispatch is working to independently confirm what statements and taunts, if any, can be heard. Reporters at the ballpark did not have access to the broadcast mentioned, and any individual taunts from fans that could have been picked up by the mic were drowned out by the crowd noise that was heard in the press box.

The Cardinals have ballpark policy that forbids racial slurs. Any fan heard yelling them will be ejected from the game, a club official said.

"Ushers would act swiftly," Cardinals spokesman Ron Watermon said. "We are firm with this, no question."

Heyward was asked after the game about the reception he received.

"Who didn't say anything?" Heyward said. "Obviously people are going to say something. There's a lot of Cubs fans here, too."