What happened: Former San Francisco 49ers linebacker Aldon Smith has passed away at the age of 36. The news sparked an outpouring of grief across the NFL community following reports of his tragic passing on Sunday. No cause of death has been immediately disclosed by his family or representatives.

Why it matters: Smith was once the most dominant defensive force in the league, setting an NFL record with 33.5 sacks in his first two seasons. His time in San Francisco was marked by elite production, helping anchor a defense that reached three consecutive NFC Championship games and Super Bowl XLVII. His career remains one of the great "what-if" stories in league history due to his immense natural talent.

What to watch: The San Francisco 49ers and the NFL are expected to release formal statements honoring the star defender. Details regarding memorial services have not yet been announced by the family.