NFL players have signaled to owners that they would be open to discussing expanding the regular season to 17 games as part of a new collective bargaining agreement as long as the players' share of league revenue under the new deal increased by a sufficient amount, sources told ESPN.

The owners' proposal to expand the regular season from 16 to 17 games would begin in 2022 and would come with a shortened, three-game preseason, multiple sources told ESPN.

The owners' most recent revenue-split proposals, which were presented during a negotiating session two weeks ago in Jacksonville, are not satisfactory to the players, sources told ESPN. But the league reached out to the NFLPA following the owners' meetings earlier this week in Fort Lauderdale, and the two sides are currently attempting to schedule a formal negotiating session for some time in the near future.

One key issue that has arisen, sources said, is the cost of the new Rams and Chargers stadium in Los Angeles. Initial cost projections for that stadium were around $2.5 billion, but according to sources they are now projected to exceed $5 billion. As a result, the owners are trying to build into the new deal the ability for them to designate revenue credits off the top of the pile for stadium costs (specifically, but not exclusively, in Los Angeles).

Two weeks ago in Jacksonville, the owners submitted two different proposals. One would increase the players' share of revenue from 47% to 47.7% and would not include the L.A./stadium credits. This structure would mirror that of the current CBA, signed in 2011, which stipulates the players' share of revenue not drop below 47% at any point during the deal.

The players pushed for that model in the 2011 talks because they believed it put a cap on the owners' ability to take out money for stadium construction and new stadium renovation, and it worked. At this point, the owners cannot take out any more stadium money without pushing the players' share of revenue below 47%, which means they've effectively used all of their stadium credits.

The second proposal would increase the players' share of revenue to 48.25%, but would allow the owners much greater freedom to deduct stadium-related costs off the top. The examples that were cited in the proposals included a revenue projection of $16.5 billion. Under the first proposal above, players would get 47.7% of that figure, or about $7.87 billion per year. Under the second, players would get 48.25% of a lower figure, estimated at $16.4436 billion, which works out to $7.934 billion.

The numbers end up being very similar, but the players' side prefers the first model, because they fear the owners would be able to take advantage of a model that allows them to take money off the top for stadium costs. Regardless, sources told ESPN, the revenue-split figures in both proposals are far lower than what the players have in mind in exchange for expanding the regular season -- a concept they have opposed privately and publicly for years.

Sources familiar with the discussions at the owners meetings this week in Fort Lauderdale said the owners aren't entirely united on how to proceed. Some favor an expanded season enough that they favor offering the players a greater share of revenue in order to get it done; others are lukewarm on the idea of expanding the season and would prefer to hold the line on the financial piece.

Additionally, the proposal for a 17-game regular season is not fully formed. While there has been some discussion about the details -- every team getting a bye before its Thursday night game, the Super Bowl floating back to President's Day weekend, players getting paid on a 52-week schedule as opposed to just during the regular season -- those details are not yet included in any formal proposal made by either side. So even if they could agree on expanding the season, there would still need to be significant discussion on how that would work.

There has been enough progress made on other issues that, if the financial structure is agreed upon, a deal could come together quickly, sources said. Both sides want it done during the season. The owners would like it done so they can focus on new TV deals; the players would like it done because they will be electing new leadership in March.

Current NFLPA president Eric Winston is not on a team, and their rules say their president must be. The players like a lot of the changes that would be included in the new deal -- such as benefits programs, drug policy changes, new rules governing free agency and the offseason -- and would want those to start as soon as possible.

The current collective bargaining agreement expires in March 2021.

Seth Wickersham contributed to this report.