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Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, still is not 100% sure football games are going to be played later this year. He spoke to CNN on Thursday and explained that he believes football teams will need to live inside a "bubble" in order to be able to play their respective 2020 seasons.

Due to the coronavirus pandemic, he explained, football teams likely would need to mirror what the NBA and MLS are doing with creating closed off communities for athletes.

The NFL has already expressed their feelings on a bubble. They do not think it is "practical or appropriate," the league chief's medical officer Dr. Allen Sills said this week.

Fauci disagrees. Here's what he said, via CNN:

"Unless players are essentially in a bubble -- insulated from the community and they are tested nearly every day -- it would be very hard to see how football is able to be played this fall. If there is a second wave, which is certainly a possibility and which would be complicated by the predictable flu season, football may not happen this year."

The NFL's Chief Medical Officer Allen Sills responded to Fauci's most recent comments, saying the league is willing to make adjustments as needed.

"Make no mistake, this is no easy task. We will make adjustments as necessary to meet the public health environment as we prepare to play the 2020 season as scheduled with increased protocols and safety measures for all players, personnel and attendees," Sills said. "We will be flexible and adaptable in this environment to adjust to the virus as needed."

The NFL Players Association also released a statement on Fauci's comments, from NFLPA Medical Director Dr. Thom Mayer: 

"Dr. Anthony Fauci's words carry important weight as he has served our country with expert guidance and moral clarity through many crises.

"As we have communicated to our players throughout the spring, we know there are significant challenges to the operation of football during a global pandemic. So far, we have been guided and made decisions based on the best available science and current state of infections and hospitalizations. Our joint task force is comprised of expects in multiple areas who are working everyday with health and safety in mind. 

"In addition to stringent protocols and workplace safety, we continue to reinforce the importance of widely available testing. It is not just a key to restarting football, but also a matter of public health. While the information we currently have indicates it will not be an issue in the near future, we all agree that ethically, we can not as a non-essential business, take resources away from our fellow Americans. 

"We will continue to update you as we move forward through the summer."  

According to ESPN, the NFL Players Association has told its members they would be tested around every three days, and anyone testing positive would be quarantined. The league currently plans to start games on time, though there have been rumors that the preseason could be shortened.

When it comes to college football, the NCAA approved a six-week practice plan on Wednesday beginning in July. As of now they are expecting to start the season as scheduled.

Fauci first said in early May that he was skeptical about carrying out football seasons in 2020 due to the nature of the game. 

"I say you can't have a season — it's impossible," were Fauci's exact words then. "There's too much infection out there. It doesn't matter what you do. But I would hope that by the time you get to September it's not gonna be the way it is right now.