Uniform number (American football) - Wikipedia
Tom Brady rips NFL's new jersey number rule before Cowboys game - Sports Illustrated
NFL players can now wear No. 0 among rule changes
New NFL jersey numbers, explained: What to know about league's rule change for 2021
NFL players can now wear No. 0 among rule changes
Which NFL players are changing jersey numbers? Track every switch around the league
NFL owners pass rule expanding eligible jersey numbers for certain positions
New jersey numbers for players and other rule changes for 2021 - Hogs Haven
Single-Digit Jerseys Should Be the NFL's Most Exclusive Club - The Ringer
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