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.

If one event can dramatically alter even the most sustainable team-building strategy, is it even possible to maintain a championship window?

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