The NFL and the NFL Players Association have extended daily coronavirus testing for players and staff until September 5 - five days before the season opener.
The league has conducted 109,075 COVID-19 tests among players, staff and coaches since the start of training camps up until Tuesday, with an overall positive rate 0.46% and a positive rate among players of 0.81%.
If the positive rate from the first stretch of daily testing since their arrival at training camp last month was below 5 percent, the plan had been to shift to testing every other day.
"Our goal is all the same: to have the safest possible environment for everyone," NFL Chief Medical Officer Allen Sills said.
"We want to try to ensure that there's no one - player, coach, staff member, official, anyone - who steps onto a field with an active COVID infection."
Sills said a total of 53 new positives were confirmed among players when they arrived at training camp last month.
He added that he was not aware of any individual who was "seriously ill" from COVID-19, adding that not every positive necessarily meant a person was "actively infected."
The league continues to enforce social distancing measures ahead of its September 10 season start.
More than 60 players have opted out of playing this season, according to media reports, amid concerns over the impact of the coronavirus pandemic.
Meanwhile, the Washington Football Team said on Tuesday it would not allow any fans to attend out of an "abundance of caution," but added that it would re-evaluate the decision if conditions improved.
The New Orleans Saints said on Wednesday that they would not permit attendees at their September 13 home opener, becoming the latest franchise to limit spectators at games, adding that they would "continuously monitor trends" to evaluate whether they could welcome fans at their September 27 home game against the Green Bay Packers.
"Although the current guidance we have received from our government leaders suggest this to be unlikely, we remain prepared to host fans if allowed," the team said in a statement.
But the Dallas Cowboys, which in July was again ranked by Forbes as the most valuable sports team in the world, "plan on playing all of our football games and we plan on playing them in front of our fans" at AT&T Stadium, owner Jerry Jones said on Wednesday.
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