The medical director for the NFL Players Association is advising players to avoid working out with teammates to prevent the spread of the coronavirus.

Dr. Thom Mayer said in a statement Saturday that the NFLPA is working on safety protocols for training camps, which are set to begin in late July.

"Please be advised that it is our consensus medical opinion that in light of the increase in COVID-19 cases in certain states that no players should be engaged in practicing together in private workouts," Mayer said in the statement. "Our goal is to have all players and your families as healthy as possible in the coming months."

Around 10 NFL teams have reported positive coronavirus tests for at least one of their players, a source told ESPN's Jeremy Fowler, prompting the NFLPA to release the statement.

The NFL and NFLPA share a database that updates each time a team reports a positive test, and there's been an uptick over the last two weeks. Teams can administer tests for players who were already rehabbing injuries in the team facility, thus permitted to be there, or when a player discloses symptoms.

Multiple veteran NFL players tell ESPN that, despite optimism for the season, the sheer volume of positive tests in college and professional football is alarming for game weeks, and how the virus can deplete a roster.

A number of quarterbacks, including the Buccaneers' Tom Brady, the Giants' Daniel Jones and the Jets' Sam Darnold, have organized throwing workouts with teammates in the recent past.

On Saturday, sources told ESPN's Adam Schefter that at least two Buccaneers players had tested positive for COVID-19. Tampa Bay said in a statement that some team members had tested positive, without identifying whether it was players or staff, and that affected areas were being closed for extensive sanitizing.

The NFL and NFLPA are continuing to work to finalize protocols for players' safe return to team facilities for training camp next month.