Tim Sharp/Associated Press

Dallas Cowboys owner Jerry Jones and New England Patriots owner Robert Kraft reportedly led a discussion at the latest collective-bargaining session with the National Football League Players Association about expanding the NFL regular season to 18 games.

Andrew Beaton of the Wall Street Journal reported Thursday the players' union "resisted" the idea, which could create "potentially billions of dollars annually." The owners also floated a proposal that would cap each player's appearances at 16 per season as a possible compromise.

NFLPA president Eric Winston, a longtime offensive tackle who's currently a free agent, told Beaton increasing the number of games wouldn't address any of the players' concerns, led by non-guaranteed contracts and health coverage following retirement.

"They're looking at it like, 'Hey, get back into the mine and start mining coal,'" Winston said.

Beaton reported a union analysis of a potential 18-game schedule suggested it could reduce the average career span from 3.3 years to 2.8 years, a critical drop because players don't become eligible for NFL pensions and post-playing health insurance until they complete three years in the league.

"No players are banging down my door asking me to think about [an 18-game schedule]," Winston told Beaton.

"I don't see an 18-game schedule -- under any circumstance -- being in the best interest of our players," NFLPA executive director DeMaurice Smith said, per Cameron Wolfe of ESPN. "If somebody wants to make an 18-game proposal, we'll look at it. I haven't seen anything that makes me think that it would be good for the players."

Although the league's current CBA runs through the 2020 season, the sides have started meeting early with hopes of avoiding a potential lockout or strike in the coming years.

The early discussions suggest an 18-game schedule could become a sticking point, and it could create unintended consequences if the 16-game cap is adopted.

For example, a family that pays to see the Cowboys' Ezekiel Elliott, the Patriots' Tom Brady or the Kansas City Chiefs' Patrick Mahomes only to find out he's a healthy scratch that week isn't likely to take kindly to the decision. The same goes for all the NFL's superstars.

While fans would miss out on seeing the sport's best twice a year, the NFLPA fears the change could also hurt the players at the opposite end of the spectrum given nearly 60 percent of the players make the league's minimum salary, according to Beaton.

But with billions of dollars potentially available, the issue is likely to remain at the forefront of talks.