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.

For Lillard — and now possibly Tatum, depending on what the MRI and other exams show — injuries could be part of the story next season as well.

Tatum underwent Achilles’ repair surgery on Tuesday after going down in Game 4 at Madison Square Garden.