The NFL Players Association on Friday sent a letter to the NFL asking for the immediate reinstatement of Vikings running back Adrian Peterson, a league source confirmed.

The union contends that Peterson’s time on the NFL’s commissioner’s exempt list was supposed to end as soon as his legal situation was resolved in Texas. On Tuesday, Peterson avoided jail time by pleading no contest to a misdemeanor charge of recklessly injuring his 4-year-old son.

But a NFL spokesman told the Star Tribune that the league contends that it is not in violation of the agreement it made with Peterson, his representation and the NFLPA back in September.

“The agreement was for Peterson to be on paid leave until the completion of his legal proceeding, at which time the matter would be reviewed for potential discipline under the personal conduct policy,” the spokesman said. “No discipline would be processed until there was a resolution by the court. Following the completion of his legal proceeding, we promptly requested information from Peterson and are awaiting its receipt. We expect to have an orderly and expeditious process by which his case will be reviewed and resolved.”

In a statement released Monday on the team's web site, the Vikings said: "In regards to Adrian Peterson's status with the Minnesota Vikings, at this time his potential reinstatement is under NFL guidelines. As an organization, we respect and understand the league’s process. In the interim, our focus is on the team and preparing for this weekend's game against the Bears"

The NFL informed Peterson on Thursday that he would remain on the commissioner’s exempt list while his case was reviewed under the NFL’s personal conduct policy. The NFL has asked Peterson for information on the case, and he could be given the opportunity to have a meeting with the league before a decision is made on whether he will be punished by NFL Commissioner Roger Goodell.

After that news broke Thursday, the NFLPA issued a statement saying that the union would “pursue any and all remedies” to ensure that Peterson’s case was being handled properly.

“Our union worked with the NFL, the Minnesota Vikings and Adrian’s representatives on a mutual agreement pending the adjudication of his legal case,” the statement said. “Now that his legal matter is resolved, we believe it is Adrian’s right to be treated in a manner that is consistent with similar cases under our collective bargaining agreement. We will pursue any and all remedies if those rights are breached.”

Meanwhile, the Vikings must wait for the NFL to announce any punishment for Peterson before officially deciding whether they will welcome him back to the team.

A team source on Sunday denied an NFL Network report that said an “internal battle was brewing” at Winter Park over Peterson’s future with the team. The source said the Vikings are “100 percent unified” and support Peterson, but they are “respecting the process” as the league reviews Peterson under the personal conduct policy.

ESPN first reported that the NFLPA had sent the letter to the NFL.