Social media detectives noticed that San Francisco 49ers head coach Kyle Shanahan has aged aplenty in just eight year.

San Francisco 49ers head coach Kyle Shanahan looks as if he has aged more than he should have in the last eight years.

Kyle, on the other hand ... A viral side-by-side comparison of Shanahan from when he first took over the 49ers in 2017 to now paints a telling picture. The youthful, fresh-faced play-caller ...