As part of the agreement the league and the NFL Players Association reached last week, players have until 4 p.m. ET on Thursday to give written notice of their intention to sit out the upcoming season.

Players can choose to sit out a year either because they’re deemed at high risk of developing health complications from coronavirus or because they voluntarily choose not to participate in football activities in the upcoming season.

To fall into the former category, players must have been previously diagnosed for one of 15 risk factors as outlined by the Centers for Disease Control. The list includes cancer, Type 2 diabetes, sickle cell and liver diseases, asthma, hypertension, cystic fibrosis, neurologic conditions such as dementia, pulmonary fibrosis, COPD or cerebrovascular disease.

Players who have undergone organ transplants that may compromise their immune systems or have serious heart conditions are also considered high-risk.

Unlike in the MLB, where players can opt out at any time, the NFL requires players to make their decision well ahead of the start of the season.

The decision is irrevocable and players can’t change their minds after the deadline, unless a family member becomes seriously ill with COVID-19 or whether the player himself is diagnosed with a high-risk condition.

High-risk players who have to sit out the season will receive a $350,000 salary, while players who voluntarily choose to opt out will receive a $150,000 stipend that will be considered as a salary advance and will count against the team’s 2020 salary cap.

While players in both categories will continue to have health insurance, only the players in the high-risk category will earn an accrued season towards free agency as well as all benefits and minimum salary credit for a credited season.

Additionally, undrafted rookies will not qualify for the stipend if they choose to opt out.

Since Kansas City Chiefs offensive lineman Laurent Duvernay-Tardif became the first player to announce he would sit out the upcoming campaign on July 24, several players have followed suit.

As it stands, the Atlanta Falcons, Los Angeles Rams, Pittsburgh Steelers and Tampa Bay Buccaneers are the only four franchises to not have players opting out.

Aside from Duvernay-Tardif, the Chiefs will also be without Super Bowl LIV hero Damien Williams.

The New England Patriots have lost eight players, with star linebacker Dont’a Hightower, running back Brandon Bolden and fullback Danny Vitale all opting out along with guard Najee Toran, offensive lineman Marcus Cannon, safety Patrick Chung, wide receiver Marqise Lee and tight end Matt LaCosse.

The Cleveland Browns will be without guards Drew Forbes and Colby Gossett, offensive tackle Drake Dorbeck and defensive tackle Andrew Billings, while the Dallas Cowboys have lost cornerback Maurice Canady, wide receiver Stephen Guidry and fullback Jamize Olawale.

The New York Jets will be without star linebacker C.J. Mosley and offensive lineman Leo Koloamatangi, while the New York Giants have lost wide receiver Da’Mari Scott, cornerback Sam Beal and offensive tackle Nate Solder, who is a cancer survivor and whose son is currently battling cancer.

Here’s a complete list of all the players who will sit out the 2020 season as of Thursday, August 6. (The asterisk denotes high-risk players).

Arizona Cardinals: OL Marcus GilbertBaltimore Ravens: OT Andre Smith, KR De’Anthony ThomasBuffalo Bills: DT Star Lotulelei, CB E. J. GainesCarolina Panthers: LB Jordan Mack, LB Christian MillerChicago Bears: DT Eddie Goldman, S Jordan LucasCincinnati Bengals: OT Isaiah Prince, DT Josh TupouCleveland Browns: G Drew Forbes, OT Drake Dorbeck, DT Andrew Billings, G Colby GossettDallas Cowboys: CB Maurice Canady, WR Stephen Guidry, FB Jamize OlawaleDenver Broncos: DL Kyle Peko, RT Ja’Wuan JamesDetroit Lions: DT John Atkins, WR Geronimo Allison, C Russell BodineGreen Bay Packers: WR Devin FunchessHouston Texans: DL Eddie VanderdoesIndianapolis Colts: LB Skai Moore, CB Marvell Tell, DB Rolan MilliganJacksonville Jaguars: DT Al Woods, DE Lerentee McCrayKansas City Chiefs: RB Damien Williams, OG Laurent Duvernay-TardifLas Vegas Raiders: CB D. J. Killings, DE Jeremiah Valoaga, LB Ukeme EligweLos Angeles Rams: OT Chandler BrewerMiami Dolphins: WR Allen Hurns, WR Albert WilsonMinnesota Vikings: DT Michael PierceNew England Patriots: RB Brandon Bolden, S Patrick Chung, OT Marcus Cannon*, LB Dont’a Hightower, C/G Najee Toran, FB Danny Vitale, WR Marqise Lee, TE Matt LaCosseNew Orleans Saints: TE Cole Wick*, TE Jason Vander LaanNew York Giants: WR Da’Mari Scott, CB Sam Beal, OT Nate SolderNew York Jets: LB C. J. Mosley, OL Leo KoloamatangiPhiladelphia Eagles: WR Marquise GoodwinSan Francisco 49ers: WR Travis BenjaminSeattle Seahawks: OL Chance WarmackTennessee Titans: OT Anthony McKinneyWashington Football Team: DL Caleb Brantley*, LB Josh Harvey-Clemons

The COVID-19 outbreak has ravaged the U.S. over the last four months. As of Thursday morning, over 4.82 million cases of coronavirus had been reported in the U.S.

Of the over 708,400 deaths recorded worldwide so far, more than 158,300 have been in the U.S., according to Johns Hopkins University, which has been tracking the outbreak using combined data sources.

There have been almost 18.8 million confirmed cases globally since the outbreak of coronavirus was first identified in Wuhan, a city located in China’s central Hubei province, late last year.