ESPN has apologized after playing the song "Dixie" to accompany a Civil War-themed Andrew Luck graphic during the Colts game on Saturday.

The network issued an apology on Sunday to Sporting News and said it did not originally plan to play the song when it first produced and approved the graphic. A staffer added the song last minute in the production truck and ESPN has addressed the issue with the employee, according to Sporting News.

"It was a mistake to use this song. We regret having done so and we apologize," ESPN spokesman Josh Krulewitz told Sporting News in a statement.

The graphic aired during Saturday's broadcast of the AFC Wild Card game between the Colts and Texans. It depicted Luck as a Union general being protected by both Union and Confederate soldiers. Many viewers called out ESPN on Twitter for the graphic's racial insensitivity.

The graphic was still on ESPN's NFL account on Twitter by the time of publication on Sunday. It was based on the parody Twitter account @CaptAndrewLuck, which pretends Luck is a Civil War officer writing letters to his mother. The account has over 450,000 followers.

The Colts beat the Texans 21–7 on Saturday to advance to the divisional round. Indianapolis will face the Chiefs on Jan. 12 in Kansas City. Kickoff is slated for 4:35 p.m. ET.