Throughout the off-season, the N.F.L. had stopped short of requiring that its players and other team personnel receive a Covid-19 vaccination, instead strongly encouraging inoculation.
With training camps starting in earnest next week and the regular season less than two months away, that approach has shifted.
Commissioner Roger Goodell on Thursday sent a memo to all 32 teams outlining Covid-19 guidelines for the 2021 season that detail drastic penalties for teams with unvaccinated personnel, including the forfeiture of games. Any forfeits could result in players’ not being paid — if their infections are known to have caused an outbreak.