Adam Schefter says that the NFL needs to be tougher with domestic violence and that if Ezekiel Elliott's six-game suspension is not overturned, then it could turn into a season-long legal fight. (2:13)

Schefter: It would be embarrassing for NFL if Elliott suspension is overturned (2:13)

The NFLPA filed a request for a temporary restraining order in the Eastern District of Texas, calling for the courts to block any suspension of Dallas Cowboys running back Ezekiel Elliott upheld by NFL arbitrator Harold Henderson, according to a court filing obtained by ESPN.

The NFLPA's filing calls for the court to vacate any suspension of Elliott, accusing the league's appeals process of being "fundamentally unfair" and citing new facts revealed during this week's hearing that wrapped up Thursday. Elliott has been suspended for six games for violating the league's personal conduct policy.

A source told ESPN's Josina Anderson that Elliott's side will file more paperwork Friday.

"[We] have to file another set of papers formally seeking the temporary, which will happen later today. Hearing for temporary order likely Tuesday after Harold [Henderson] rules," the source said.

If Henderson rules that Elliott should remain suspended for any stretch of games, the court then can decide to stay the suspension while it reviews the matter, and Elliott could potentially be allowed to play while the case works its way through the courts.

In the filing, the NFLPA alleges "there was a League-orchestrated conspiracy by senior NFL executives ... to hide critical information -- which would completely exonerate Elliott" in his domestic violence case.

"During the course of the past 13 months and culminating in the last three days of the appeal process, we have witnessed some of the most egregious violations of legal due process in connection with the NFL's investigation of Mr. Elliott," read a statement from Elliott's attorneys Frank Salzano and Scott Rosenblum.

"Not only did the underlying facts not support the false allegations made against Mr. Elliott, but the process in which they were gathered and adjudicated were fundamentally unfair. Mr. Elliott looks forward to being completely vindicated and will continue to explore all other legal options to redress the reputational and monetary harm that he has suffered."

According to the filing, Kia Wright Roberts, the NFL's director of investigations, testified Tuesday that she was the only NFL employee who interviewed the running back's accuser, Tiffany Thompson, during the investigation and that she would not have recommended discipline for Elliott based on what she found.

Roberts told Lisa Friel, who investigates domestic violence cases for the NFL, of her views, but was never allowed to convey them to NFL commissioner Roger Goodell or the "independent advisors."

The NFLPA says Roberts concluded after reviewing all evidence that Thompson "was not credible in her allegations of abuse," according to the filing.

"The withholding of this critical information from the disciplinary process was a momentous denial of the fundamental fairness required in every arbitration and, of course, does not satisfy federal labor law's minimal due process requirements," the union wrote.

NFL spokesman Joe Lockhart said Friday morning that it's "unequivocally, absolutely false" that Goodell was not aware of Roberts' findings in the investigation before he imposed discipline.

"The idea that this was a conspiracy is false," Lockhart said. "The credibility issues were addressed at length in the investigative report. Kia Roberts' points were made very clearly. The 160-page report included a fulsome description of the credibility problems of both Tiffany Thompson and Ezekiel Elliott." ]

Lockhart said the court will have to decide whether the league adhered to the CBA in its investigation, and the league obviously believes it did.

The NFLPA also asserted that Elliott and the union were denied the rights of a fair procedure when Henderson would not grant their request to have Thompson testify. Elliott did testify at this week's appeal hearing.

"As such, not only was Elliott denied the most fundamental rights to be able to confront his accuser and to have her credibility assessed against his, the arbitrator also rendered himself incapable of directly assessing the credibility of Thompson -- which was critical to the fairness of the proceeding," the NFLPA wrote.

In addition, the NFLPA questioned Henderson's refusal to have Goodell testify in the appeals hearing, saying: "Without testimony from the Commissioner, it was not possible to determine the full impact of the conspiracy, or precisely what the Commissioner knew or did not know about his co-lead investigator's conclusion that there was not sufficient credible evidence to proceed with any discipline under a League Personal Conduct Policy."

Cowboys owner and general manager Jerry Jones has raised questions about whether Elliott harmed Thompson, saying Tuesday, "It's a very complicated issue because you have no evidence here."

On Friday, Jones, appearing on 105.3 FM in Dallas, withheld more comment on the current state of the case. "The best thing for me to do is not to comment," Jones said.

When asked if he would at a later time, Jones responded: "Believe you me, I will."

Elliott was the NFL's 2016 rushing leader as a rookie. The Cowboys' season opener is Sept. 10 against the New York Giants.

The Associated Press contributed to this report.