The NFL claims that the rate of concussions among players fell by 25 percent this season.

Data provided to The Associated Press by the NFL ahead of its annual pre-Super Bowl health and safety news conference Thursday shows there were 111 concussions in games during the 2014 regular season, down from 148 in 2013, and 173 in 2012, a 36 percent drop over that three-year span.

"Players are changing the way they're tackling," NFL Senior Vice President of Health and Safety Policy Jeff Miller said. "They're changing the way they play the game."

A total of 59 concussions were caused by helmet-to-helmet or shoulder-to-helmet hits this season, the league's data says, almost exactly half as many as two years ago.

"With all the technological innovations that we've had over the past few years, I'm surprised the numbers keep going down," St. Louis Rams team doctor Matthew Matava said. "Because you'd think, with more vigilance, you'd see more of any sort of condition."

The NFLPA has filed a non-injury expedited grievance against the NFL to challenge the league's new personal conduct policy.

The union maintains that the policy is in violation of the collective bargaining agreement and seeks a cease and desist order to enjoin implementation of the policy.

In the grievance, the NFLPA emphasizes that "the NFL adopted the new Policy without the consent, and over the objections, of the NFLPA."

The NFL responded to the union's grievance in a statement Friday morning.

"The league's revised conduct policy was the product of a tremendous amount of analysis and work and is based on input from a broad and diverse group of experts within and outside of football, including current players, former players, and the NFL Players Association," the statement read.

"We and the public firmly believe that all NFL personnel should be held accountable to a stronger, more effective conduct policy. Clearly, the union does not share that belief."

The Oakland Raiders are close to signing a one-year extension to remain at the Coliseum in Oakland in 2015.

Mark Davis has had discussions about a possible relocation of the Raiders to San Antonio or Los Angeles.

“We want to be here,” Davis said. “We’re not using any other place, city or whatever, as leverage. It’s not that way. It’s known that no matter what we do here, it will not be as valuable or economically as great for the Raiders as if we went somewhere else. That’s known. But we still want to be here.”

Davis also said he’d be willing to spend $500 million on a new stadium. A new stadium would likely cost upwards of $1 billion.

Stan Kroenke, who bought 60 acres adjacent to the Forum a year ago, has joined forces with the owners of the 238-acre Hollywood Park site, Stockbridge Capital Group. They plan to add an 80,000-seat NFL stadium for the St. Louis Rams and a 6,000-seat performance venue to the already-massive development of retail, office, hotel and residential space, Stockbridge and the Kroenke Group told The Times.

The Rams moved from Anaheim to St. Louis in 1994 after being in Southern California since 1946.

Under their current deal, the Rams can end their 30-year lease a decade early because they have not reached an agreement with St. Louis officials on improvements to the stadium. The sides remain about $575 million apart. St. Louis is expected to offer the team a new proposal by month's end.