Arbitrator Shyam Das ruled in favor of the NFL on Tuesday evening, saying the league can keep Adrian Peterson on the commissioner's exempt list, effectively ending any chance the Minnesota Vikings running back will play again this season.

Earlier Tuesday, Peterson was suspended without pay for at least the remainder of this season. Das' ruling was in reference to a grievance Peterson had filed arguing he should have been reinstated from the exempt list as soon as there was a resolution in his child abuse case, which came with his no contest plea on Nov. 4. Das' ruling was not connected to the suspension.

A source told ESPN's Andrew Brandt that Das ruled that Peterson "failed to establish on this record that the NFL violated either the letter agreement or the CBA."

The NFL Players Association announced earlier Tuesday that it planned to appeal Peterson's suspension and sharply rebuked what it called the league's inconsistency and unfairness in the process.

Due to Das' ruling, Peterson will remain on the exempt list until the appeal of his suspension is heard.

Peterson was placed on the exempt list Sept. 18 following his indictment on felony child abuse in Texas, and was to remain on the list while his case went through the courts. On Nov. 4, Peterson pleaded no contest to misdemeanor reckless assault for injuries to his 4-year-old son with a switch, essentially resolving his case.

The NFLPA said Peterson was told his time on the exempt list would count as time served for any suspension levied, citing an unnamed NFL executive. League spokesman Brian McCarthy told The Associated Press in an email that Peterson's stay on the exempt list was taken into account.

Adrian Peterson's season is likely over after arbitrator Shyam Das ruled in favor of the NFL. Hannah Foslien/Getty Images

Peterson will not be considered for NFL reinstatement before April 15, 2015.

The Vikings released a statement earlier Tuesday saying they "respect the league's decision and will have no further comment at this time."

Goodell, however, expressed concern in his letter that Peterson does not "fully appreciate the seriousness" of his conduct.

"You have shown no meaningful remorse for your conduct," Goodell's letter said. "When indicted, you acknowledged what you did but said that you would not 'eliminate whooping my kids' and defended your conduct in numerous published text messages to the child's mother. You also said that you felt 'very confident with my actions because I know my intent.'

"These comments raise the serious concern that you do not fully appreciate the seriousness of your conduct, or even worse, that you may feel free to engage in similar conduct in the future."

The boy suffered cuts, marks and bruising to his thighs, back and on one of his testicles, according to court records. Goodell cited those injuries in his letter to Peterson.