(CNN)Jon Gruden, head coach of the NFL's Las Vegas Raiders, used racially insensitive language to describe NFL Players Association executive director DeMaurice Smith, who is Black, in an email sent in 2011, according to a report from The Wall Street Journal.
Raiders coach Jon Gruden described head of NFL players union using racially insensitive language in 2011
Gruden, who is White, was working as the lead analyst for ESPN's Monday Night Football at the time.
The Journal reported that it reviewed an email Gruden sent to the president of the Washington Football Team in which Gruden wrote, "Dumboriss Smith has lips the size of michellin [sic] tires." The email was unearthed as part of an NFL review of workplace misconduct at the Washington Football Team that took place this summer, according to an NFL spokesperson.
Gruden told the Journal that he did not remember writing the email, but did not dispute having written it.
"I'm really sorry," Gruden told the Journal. "I was upset. I used a horrible way of explaining it."
Gruden explained to the Journal that he uses the phrase "rubber lips" to describe people he thought were lying.
"I don't think he's dumb. I don't think he's a liar," Gruden backtracked to the Journal. "I don't have a racial bone in my body, and I've proven that for 58 years."
CNN has been unable to reach Gruden for comment.
DeMaurice Smith called Gruden's comment "racist" in a statement to CNN.
"This is not the first racist comment that I've heard and it probably will not be the last," Smith said. "This is a thick skin job for someone with dark skin, just like it always has been for many people who look like me and work in corporate America.
"You know people are sometimes saying things behind your back that are racist just like you see people talk and write about you using thinly coded and racist language. Racism like this comes from the fact that I'm at the same table as they are and they don't think someone who looks like me belongs. I'm sorry my family has to see something like this but I would rather they know. I will not let it define me."
Raiders owner Mark Davis described the content of the email as "disturbing" in a statement Friday.
"We were first made aware of the email late yesterday by a reporter and are reviewing it along with other materials provided to us today by the NFL," he said in the statement. "We are addressing the matter with Coach Gruden and will have no further comment at this time."
The NFL was also quick to condemn Gruden's words.
"The email from Jon Gruden denigrating DeMaurice Smith is appalling, abhorrent and wholly contrary to the NFL's values," an NFL spokesperson told CNN. "We condemn the statement and regret any harm that its publication may inflict on Mr. Smith or anyone else."