The NFL Players Association has filed a lawsuit against the NFL in U.S. District Court in Minneapolis, challenging an arbitrator's decision made Friday to uphold Adrian Peterson's suspension by the league.

The lawsuit comes as ABC News has obtained a recording of the Nov. 12 phone call between Troy Vincent and Peterson in which the NFL executive tells him that he would be reinstated after a two-game suspension and get credit for his time on the commissioner's exempt list.

Vincent made the promise with the additional request that Peterson attend a Nov. 14 meeting with commissioner Roger Goodell to discuss the child abuse case in which he pleaded no contest in Texas to misdemeanor reckless assault for physically disciplining his 4-year-old son with a wooden switch. Peterson declined to attend the meeting, however, citing uncertainty about the NFL's intent to question him, and the league issued a six-game suspension to the running back on Nov. 18.