After his legal team hammered away at his accuser’s credibility, and took its turn jabbing at investigative analysis and medical experts, the suspension appeal of Dallas Cowboys running back Ezekiel Elliott ended with a disappointment that has become familiar to NFL players. Now comes the hard part for Elliott: pulling off a legal upset that even New England Patriots quarterback Tom Brady couldn’t engineer.

That’s the task at hand for Elliott and the NFL Players Association after NFL-appointed arbitrator Harold Henderson upheld the league’s six-game domestic violence suspension of the running back – go to federal court and accomplish the lasting collective-bargaining victory that the NFL’s most famous player couldn’t.

This is the final option on the table, mounting a step-by-step comeback in federal court, hoping to strike a blow against the NFL’s broad disciplinary powers granted to the league by its collective-bargaining agreement. Unlike Elliott’s appeal, it’s a fight that won’t orbit around his guilt or innocence. Instead, it will attack the manner in which the NFL followed its own collective-bargaining guidelines and procedures when coming to Elliott’s suspension conclusion. It’s a battle of red tape, legal motions and fine print. A clash of billable hours between NFL and union lawyers. And if it advances far enough into the legal system, a marathon of depositions.

More than anything, if it’s like Brady’s deflate-gate fiasco, it will be a war of words, too.

That’s what Elliott has laid out in front of him, via some of the same legal plateaus and CBA arguments that Brady covered. Arguments that Brady lost. Plateaus that his legal team – including this same players union and same attorney, Jeffrey Kessler, ultimately surrendered. That’s part of the difficulty here for Elliott, knowing that after months of nasty legal wrangling between the union and NFL attorneys, Brady’s case cratered in a federal appeals court. And the fallout galvanized the NFL’s legal department like never before, delivering a seeming certainty that the broad disciplinary language and powers drawn upon by commissioner Roger Goodell were impenetrable. For Elliott to overcome that now would be a staggering (and very unlikely) upset for the NFL and Goodell.

So what lies ahead?

The first step will be securing a preliminary injunction against the NFL’s suspension from U.S. District Judge Amos L. Mazzant III in a hearing Friday. If Elliott can achieve the injunction, it will keep him on the football field until his federal case either exhausts all legal avenues and ends in failure, or he wins a vacation of the suspension and the NFL exhausts its own appeals.

If Elliott can’t obtain an injunction allowing him to remain on the field, he will be forced to serve his suspension while his federal case is in the system. In that case, he would seek to expedite the process and have his case against the NFL heard as soon as possible to avoid missing the entirety of his six-game suspension while litigation drags on.

As for the CBA court battle, Elliott’s legal team and the NFLPA will be charged with proving the NFL – including Goodell and the league’s four-person panel reviewing the case – committed significant errors while weighing evidence and allegations. In proving that, Elliott’s team would seek to show that his six-game suspension conclusion was “arbitrary and capricious.” In short, it’s all about the accuracy and integrity of the process.

In its initial federal case filing, the NFLPA has shown the grounds that it believes were violated in the integrity of the process. Most specifically, the union believes there was a conspiracy to withhold the contrarian opinions and analysis of lead investigator Kia Wright Roberts from Goodell and the four-person panel prior to their suspension conclusions. It’s that central point – conspiracy corrupting the league’s process – that will be the first of several footholds Elliott’s attorneys will seek to prove in court.

The strength of evidence supporting that attack remains to be seen, but in the wake of Henderson reiterating Elliott’s suspension on Tuesday, the legal team of the Cowboys’ star had already begun to plow ahead into the federal case. For the NFLPA, it’s a familiar place to be, having already fought and defeated Brady and former Minnesota Vikings star Adrian Peterson in this arena.

Elliott is officially the next man up, hoping to win the same game that other league titans couldn’t.

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