The NFL Players Association told its members in a memo Thursday that it has reached tentative agreements with the league and owners on some issues, including “significant modifications” to the league’s drug and disciplinary policies, in negotiations on a new collective bargaining agreement. Some differences still must be resolved for the CBA to be completed.

That prospective CBA could include a 17-game regular season, a reduced preseason and an expanded playoff field as proposed by the NFL, according to the memo sent to players by DeMaurice Smith, the NFLPA’s executive director.

“While we remain committed to the bargaining process, the major issues separating us are significant enough that we cannot recommend to our membership that we should accept a deal in this state at this time,” Smith wrote in the memo, a copy of which was obtained by The Washington Post and other media organizations.

Representatives of the league and the NFLPA have been negotiating for months, attempting to avoid a repeat of their bitter labor confrontation before they struck a 10-year deal in 2011. Owners locked out players before that CBA, whichruns through next season.

Since mid-November, hopes have been buoyed that a deal perhaps is within reach by the Super Bowl. If no agreement is struck by then, the next goal for the two sides appears to be early March, when the new league year begins and the free agent market opens. The NFLPA elects new player leadership at its annual meeting later that month, with former offensive lineman Eric Winston no longer eligible to serve as president. The dynamics at the bargaining table could change if there’s no deal in place by then.

There has been a feeling among those close to the discussions that an agreement remains possible, but its completion depends on the willingness of the two sides to make the final remaining compromises.

One aspect of the deal involves an arrangement by which the players would receive approximately 48 percent of league revenue under the salary cap system, according to people familiar with the negotiations. That is the central economic issue of the bargaining and if it is resolved, it is widely believed that the rest of the deal could fall into place quickly.

The NFLPA memo said there already are agreements in place on changes to the drug and player disciplinary policies. The memo did not specify the modifications, but those familiar with the negotiations have said there is likely to be a less punitive approach in the league’s marijuana policy.

Players have been seeking to reduce NFL Commissioner Roger Goodell’s authority in player discipline. Goodell is empowered to make disciplinary rulings and resolve players’ appeals of those rulings. The league and owners have been receptive to reducing Goodell’s authority in matters involving the personal conduct policy (for off-field misconduct by players) but not in cases involving integrity-of-the-game issues, according to those with knowledge of the deliberations. That could mean that players’ appeals of disciplinary measures could be resolved through third-party arbitration.

The NFLPA memo said the negotiations, “thus far have proceeded with the NFL conditioning proposed increases in economics and other improvements on a potential 17 game model, with reduced preseason games and potentially an expanded playoff schedule.”

Owners turned to the 17-game proposal after abandoning efforts to secure an 18-game regular season. It’s possible that, under a 17-game model, each team would play one neutral-site game per season. Owners believe a longer regular season would be an attractive selling point to TV networks, and serve as a significant revenue-boosting measure for the NFL, offsetting any revenue loss from a shortened preseason.

The playoff field could be increased from 12 to 14 teams, resulting in two additional opening-round postseason games (with two fewer teams being given first-round playoff byes) per year. With six first-round playoff games instead of the current four, it’s possible that one would be played on a Monday night.

According to the NFLPA memo, there also are tentative agreements with the league on provisions to increase the guaranteed portion of revenue that players would receive; increases in players’ minimum salaries and performance-based pay; changes to teams’ offseason schedules and further restrictions on hitting during training camps; reductions in fines for on-field infractions; and “significant” increases in players’ benefits.

The memo states the major issues still separating the two sides in negotiations include the maximum percentage of revenue that players could receive; team’ cash spending requirements for player payrolls; pension issues; further increases of minimum salaries; a removal of the funding rule for teams related to money being placed in escrow to cover guaranteed player contracts; rules related to players chosen in the first round of the NFL draft and restricted free agents; and a liability waiver proposed by the league.

“This is the status as negotiations continue between our union and the NFL,” Smith wrote to players. “I will update you as negotiations continue and will recommend an agreement only when our Executive Committee and I are confident it is the best available one for all players.”

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