Tom Brady tested positive for COVID-19 after Buccaneers' Super Bowl victory parade

Tom Brady shared that he has already had COVID-19 and the Tampa Bay Buccaneers quarterback warned the virus could play havoc with the 2021 NFL season.

The 44-year-old future Hall of Famer revealed he contracted COVID-19 soon after celebrating his seventh Super Bowl triumph on the team's boat parade in February.

Earlier on Sunday, Dallas Cowboys star offensive lineman Zack Martin became the first player to be ruled out of a game in the 2021 season following a positive COVID-19 test.

Cowboys’ Pro-Bowl G Zack Martin has been placed on the Reserve-COVID list and is out for Thursday night’s regular-season opener against Tampa Bay.

— Adam Schefter (@AdamSchefter) September 5, 2021

The Bucs have three players currently on the COVID-19 reserve list, including star defensive lineman Ndamukong Suh. The trio could still return in time for the season opener, but Tom Brady fears that players missing games will be a recurring theme this season.

"I think it's going to be challenging this year," Tom Brady told the Tampa Bay Times.

"I actually think it's going to play more of a factor this year than last year, just because of what we're doing now, and what the stadium is going to look like, and what the travel is going to look like, and the people in the building and the fans".

"It's not like last year, although we're getting tested like last year. I definitely think guys are going to be out at different points and we've just got to deal with it."

Why is Cowboys guard Zack Martin not available to play against Tom Brady's Buccaneers in the season opener?

Because of return-to-play protocols, six-time Pro Bowl guard Martin will miss the NFL kickoff game between the Cowboys and Tom Brady’s Buccaneers on September 9 at Raymond James Stadium.

A fully vaccinated player who tests positive can return to play after five days if he is is asymptomatic and records two negative tests 24 hours apart. An unvaccinated player has to quarantine for 10 days.

Martin only has mild symptoms, but because he does have symptoms, he will not be able to leave the protocol until the symptoms are gone. Martin is vaccinated, so the earliest he could be released from the protocol is Friday, the day after the kickoff game.

"He's frustrated, obviously," said Cowboys head coach Mike McCarthy. "But, hey, this is the world we live in right now."

Third-year lineman Connor McGovern will cover, having also stepped into the role in relief of Martin last season.

Cowboys guard Connor McGovern to start for RG Zack Martin (COVID-19) vs. Bucs. Mike McCarthy: “He’ll definitely be ready for this opportunity. ...I like the way Connor goes about his business.” McCarthy said Martin is “frustrated, obviously. But this is the world we live in.” pic.twitter.com/wPm6hN5Hji

— Michael Gehlken (@GehlkenNFL) September 5, 2021

Tom Brady and the rest of his Tampa Bay teammates are fully vaccinated, with the Bucs recently joining the Atlanta Falcons as the NFL’s only 100% fully vaccinated teams.