The NFL is modifying the league's gambling policies that will punish players more harshly for betting on their own teams while also amending rules that will allow some players, including Detroit Lions wide receiver Jameson Williams, to return to the field quicker.

Under the new policy, as disclosed in a memo from commissioner Roger Goodell that was obtained by ESPN on Friday, a player who places a bet involving his own team will be suspended at least two years. Bets placed by players on any NFL game will result in at least a one-year suspension.

Betting on non-NFL sports while at a team facility or on team-related travel will now result in a two-game suspension for a first violation, six games for a second violation and at least one year for a third.

The Las Vegas Raiders officially released defensive end Chandler Jones on Saturday.

Jones was arrested Friday in Las Vegas after a turbulent week that included multiple posts to social media. He was arrested after allegedly violating a domestic violence temporary protective order.

The Raiders said in a statement Friday they were "hopeful that Chandler Jones receives the care that he needs. He, his family, and all those involved are in our thoughts."

Alan Williams resigned as Chicago Bears defensive coordinator last week in part because of inappropriate activity, sources told ESPN's Adam Schefter.

Williams was not involved in any criminal activity, sources told Schefter, but the Bears' human resources department was part of the process that culminated in his abrupt resignation Wednesday.

A digital forensic search was conducted as part of Williams' resignation, according to sources, who added that such a process was part of the team's standard operating procedure.

Since 2011, total pay for NFL running backs and fullbacks has increased by just 11 percent compared to at least 90 percent for every other offensive position.

Last season, among the N.F.L.’s 32 teams, the 32 highest-paid running backs made an average of $5 million.

In 2013, running backs were typically the sixth-highest-paid position of what could be considered the 11 offensive starters. Now they are the eighth. Last season, on 17 of 32 teams the second-highest-paid wide receiver was paid more than the highest-paid running back.

Since 2000, only 24 percent of starting N.F.L. running backs were still starting four years later, lower than 33 percent for wide receivers and 47 percent for quarterbacks.