Rumblings about an NFL work stoppage have been percolating for months, and NFL Players Association Executive Director DeMaurice Smith has reportedly added a new wrinkle to the proceedings.

Per Liz Mullen of SportsBusiness Journal, Smith sent an email to every NFL agent saying that the union is "advising players to plan for a work stoppage of at least a year in length" when the collective bargaining agreement ends after the 2020 season.

Just 100 days from the NFL's centennial season, the looming threat of a work stoppage continues to be a hot topic in league circles.

Smith told The MMQB's Albert Breer two years ago that a lockout before the 2021 season was "almost a virtual certainty."

ESPN.com's Adam Schefter reported in January that teams were using language in new coaches' contracts to protect themselves in the event of a work stoppage that impacts the 2021 campaign.