While the injury shouldn't derail Tatum's career, it does give the Celtics a major obstacle to overcome. Boston has been to the conference finals five times and has had a pair of NBA Finals appearances—including a win last year—since 2017. Much of that success, especially over the past five or so years, has been largely due to Tatum.

On and off the court, Jaylen Brown stepped up as the leader the Celtics needed after Jayson Tatum’s season-ending injury.

Jayson Tatum's torn Achilles tendon, without hyperbole, is among the most consequential injuries in NBA history. Kevin Durant comes to mind as a similarly gifted player to suffer such an injury, but he was almost 31 when he went down in the 2019 NBA Finals.