Trent Williams: “I never directed any derogatory statement toward any referee.” (Jonathan Newton/The Washington Post)

Washington Redskins offensive tackle Trent Williams has been accused of using a racial slur at an official during Sunday’s game against the Philadelphia Eagles, according to the head of the group formed to promote diversity in hiring in the NFL. Williams denied using such a slur.

John Wooten, chairman of the Fritz Pollard Alliance, said Thursday that Williams directed the slur at umpire Roy Ellison after Ellison had attempted to stop players from both teams from directing abusive language at one another. According to Wooten, Ellison should have penalized or ejected Williams from the game but instead responded with profanity directed at Williams.

“We haven’t talked to Roy. But we are told that the players, black and white, were saying all types of things back and forth during the game,” Wooten said in a telephone interview. “Roy steps in and says, ‘Let’s stop this.’ Trent says to him, ‘[Expletive] you, N-word.’ By all rights, Roy should have thrown his flag there and said, ‘You’re gone.’ But he didn’t. He comes back at Trent with some bad language. Now Roy is wrong, too.”

Wooten said that in reaction to Williams’s alleged slur, Ellison called Williams an “ungrateful [expletive].” Wooten’s account of what Ellison said to Williams contained a different profanity than what Williams has accused Ellison of calling him.

Williams said he did not direct a racial slur at Ellison. Both Williams and Ellison are African American. “I never directed any derogatory statement toward any referee,” Williams said at Redskins Park.

“If I ever said anything like that to a ref and he feels that strongly about the word, that’s at least an unsportsmanlike [penalty]. Definitely wouldn’t just warrant a tongue-lashing from a guy that’s supposed to be the only neutral person on the field and not to feel either way about either team.

“There’s trash talk. Trash talk is trash talk. You get that in every sport."

The Fritz Pollard Alliance, which works closely with the NFL on diversity issues, said the incident — and the recent hazing and bullying controversy involving the Miami Dolphins — prompted it to issue an appeal to NFL players to stop using racially charged language.

“A number of game day officials have brought to our attention the disturbing trend of racial epithets, including the ‘N’ word, being commonly used on the field during games,” the organization said in a statement. “. . . While we understand and respect that different generations have different means of communicating, we cannot condone on any level the use of the ‘N’ word.”

Use of the word by professional athletes has drawn considerable attention and been the subject of commentary by media pundits in recent days. Miami Dolphins tackle Richie Incognito, who is white, is suspended on allegations he harassed African American teammate Jonathan Martin, including by leaving him a voice mail with a racial epithet. Los Angeles Clippers forward Matt Barnes, who is biracial, was fined $25,000 by the NBA for sending tweets with the N-word aimed at teammates during a game last week.

“Players don’t seem to understand what the N-word really means,” Wooten said. “It’s a different way of communicating now, with the rap music and everything, than we had in the old days. We have to make players understand how derogatory and ugly that word is. . . . After what happened in Miami with Incognito and Martin and what happened here, it dawned on me that we need to step up and say something about what’s going on here.

“I want our African American players to understand what’s going on. I don’t use that word ever. I’ve been called the N-word playing football, particularly in college. We felt it was time to take a stand.”

Williams said after the game he had been verbally abused by Ellison, identifying the official by his jersey No. 81. Williams said Ellison called him a “garbage [expletive], disrespectful [expletive].”

NFL officials have said the league is reviewing Williams’s allegation. An NFL spokesman declined to comment Thursday on the Fritz Pollard Alliance’s account of Sunday’s incident.

Another person familiar with the organization’s deliberations on the matter confirmed Wooten’s account. This person, speaking on the condition of anonymity because of the sensitivity of the topic, said the group’s information came from Ellison through another African American NFL official, Byron Boston.

“No one in the league [office] seems to have a different view of the facts than what I just told you,” this person said.