Sunday's scheduled NFL game between the New England Patriots and Kansas City Chiefs was postponed by the league on Saturday after positive Covid-19 tests by Patriots quarterback Cam Newton and Chiefs reserve Jordan Ta'amu.
The NFL postponed the contest to Monday or Tuesday in the wake of the positive tests for the reigning Super Bowl champion Chiefs, who closed their facility according to the NFL Network, and Patriots, who altered plans to travel to Kansas City for the game.
"In consultation with infectious disease experts, both clubs are working closely with the NFL and the NFLPA to evaluate multiple close contacts, perform additional testing and monitor developments," the league said in a statement.
"All decisions will be made with the health and safety of players, team and gameday personnel as our primary consideration."
The Chiefs-Patriots clash marks the second game originally set for this weekend postponed by Covid-19 positive tests.
The Tennessee Titans and Pittsburgh Steelers contest was moved to October 25 after first being delayed to Monday or Tuesday by the NFL before additional positive results were returned.
If the Chiefs (3-0) are forced to play Tuesday, the Patrick Mahommes-led squad would be looking at three games in NFL days with their next contests set for October 11 at home against Las Vegas and four days later at Buffalo.
The first sign of trouble came when the Patriots announced a player had tested positive, his identity later confirmed as star run-pass threat Newton when he was placed on Covid-19 reserve, ensuring he would not play this weekend.
Newton replaced Tom Brady as the signal caller for the Patriots (2-1) this season after Brady spent 20 years with New England, winning six Super Bowl titles.
"Late last night, we received notice that a Patriots player tested positive for COVID-19," the Patriots said in a statement.
"The player immediately entered self-quarantine. Several additional players, coaches and staff who have been in close contact with the player received point of care tests this morning and all were negative for COVID-19.
"We are in close consultation with the NFL as well as our team of independent doctors and specialists and will follow their guidance regarding our scheduled trip to Kansas City and game against the Chiefs.
"The health and safety of our team, as well as our opponent, are of highest priority."
Newton, a 31-year-old from Atlanta and the NFL's 2015 Most Valuable Player, was placed on the Covid-19 reserve list.
In three games with the Patriots this season, he has completed 62-of-91 passes for 714 yards and two touchdowns with two interceptions while rushing 35 times for 149 yards and four touchdowns.
After Newton's positive test was revealed, the NFL announced a positive test on the Chiefs, which the league's TV network said was returned by practice squad quarterback Ta'amu.
Contract tracing and more testing was being done on both squads.
Meanwhile, the Tennessee Titans' outbreak grew worse on Saturday as the team announced another player and two more staff members had tested positive for Covid-19.
In all, 16 members of the Titans have tested positive for the deadly virus this week, eight players and eight other employees.