The Buccaneers had already ruled Brady out for their first preseason game against the Miami Dolphins last Saturday prior to his reported absence on Thursday.

Brady, who turned 45 last week, announced his retirement, then un-retirement this offseason ahead of his 23rd NFL season.

Brady is the NFL's all-time passing leader for yards (84,520) and touchdowns (624), as well as quarterback wins (243), among numerous other records.

The San Mateo native spent his first 20 seasons with the New England Patriots, leading the franchise to an NFL record six Super Bowl championships (tied with the Steelers), before joining the Buccaneers as a free agent in March 2020, which resulted in Tampa Bay winning its second Super Bowl in franchise history, becoming the first NFL team to win a Super Bowl in its home stadium, in February 2021.

Brown hasn't played in an NFL game since stripping off his uniform and running off the field during the Tampa Bay Buccaneers game against the New York Jets at MetLife Stadium on January 5 and being released by the Buccaneers the following day.

In March, Brown said he wanted to "retire as a Pittsburgh Steeler" several years after a tumultuous departure from the franchise in which he found his most NFL success.

"Just wanna retire a Steeler," Brown initially tweeted on Monday (May 16). "Not play jus [sic] retire so we clear."

Brown was traded by the Steelers in 2019 after reports that he was dissatisfied with his situation.

The Miami native was later cut by Pittsburgh's trade partner, the then-Oakland Raiders, prior to ever appearing in a regular-season game, having since spent several games in 2019 with the New England Patriots and the majority of the last two seasons with the Buccaneers, with both tenures ending in controversy.

Brown was selected by the Steelers at No. 196 overall in the sixth round of the 2010 NFL Draft and quickly emerged as one of the league's best receivers during his nine seasons in Pittsburgh.

The 33-year-old was a four-time First-team All-Pro (2014-17), a Second-team All-Pro in 2013, and a seven-time Pro Bowl selection (2011, 2013-18), having led all NFL players in receiving yards twice (2014, 2017), receptions twice (2014, 2015) and receiving touchdowns in 2018.

After being released by the Bucs in January, Brown has served as the president of Kanye West's sports fashion line within his Donda Sports creative content company, as well as continued to focus on his own music career.

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