With every season that passes, Drew Brees places himself into an increasingly smaller group.



It’s not just the NFL passing records, of which Brees holds many (if not most). It’s not the fact that Brees undoubtedly will enter the Pro Football Hall of Fame in short order after he finally decides to retire.



Those are all rare and special things. But Brees, who announced his return to the NFL for the 2020 season on Tuesday, is now a member of a group so small that whatever he does next could greatly define opinions on the next decade of quarterback play.



Just how long can a starting quarterback be successful in this league? What’s the oldest age that a quarterback could feasibly push himself to still play at a high level?



These questions haven’t been given a firm answer yet because to date, there haven’t really been many quarterbacks who played, and started, well into their 40s.



In the history of the NFL, only 21...