TEMPE, Ariz. - Arizona Cardinals cornerback Josh Shaw was suspended indefinitely -- through at least the 2020 season -- for betting on NFL games on multiple occasions this season, the NFL announced Friday.

Shaw has not played a down this season for the Cardinals. He was put on injured reserve on Aug. 25 with a shoulder injury.

He can file an appeal of the suspension within three days.

The NFL's investigation into Shaw did not uncover evidence that indicated he used inside information or that any game was compromised. The NFL also announced that Shaw's teammates, coaches and other players around the league were not aware of Shaw's gambling.

Shaw has not been around the Cardinals much this season.

"The continued success of the NFL depends directly on each of us doing everything necessary to safeguard the integrity of the game and the reputations of all who participate in the league. At the core of this responsibility is the longstanding principle that betting on NFL games, or on any element of a game, puts at risk the integrity of the game, damages public confidence in the NFL and is forbidden under all circumstances," NFL commissioner Roger Goodell said. "If you work in the NFL in any capacity, you may not bet on NFL football."

Betting on football is one of 10 restrictions on legal gambling that the NFL laid out in its gambling policy.

"All NFL Personnel are prohibited from placing, soliciting, or facilitating any bet, whether directly or indirectly through a third-party, on any NFL game, practice or other event," the policy states. "This includes betting on game outcome, statistics, score, performance of any individual participant, or any other kind of 'proposition bet' on which wagering is offered."

Shaw can petition for reinstatement on or after Feb. 15, 2021, if his possible appeal is denied.

Suspensions of NFL players for betting are rare. The highest-profile case was in 1963 when Paul Hornung of the Green Bay Packers and Alex Karras of the Detroit Lions were banned for the entire season. Both were reinstated the following season and Hornung went on to make the Hall of Fame.

In the most recent case, Baltimore Colts quarterback Art Schlichter was suspended in 1983 for betting on NFL games and other sporting events. He, too, was reinstated the following year.

The Cardinals signed Shaw on March 18 to a one-year contract worth $850,000. He has made more than $3 million in his career.

Shaw, 27, was drafted by the Cincinnati Bengals in the fourth round of the 2015 draft. After playing his first three seasons in Cincinnati, Shaw split time between the Kansas City Chiefs and Tampa Bay Buccaneers last season.

Shaw made headlines in 2014 while at USC when he said he suffered a high ankle sprain jumping from a second-story apartment to save his 7-year-old nephew who was struggling in a pool. Shaw later admitted to lying about that story and was suspended indefinitely by the school.

Information from The Associated Press was used in this report.