1925: The facemask is added to leather football helmets as a response to the Decatur Staleys' unstoppable "punch in the face" defensive technique

1963: The NFL begins research on impact-resistant composite materials in an effort to devise a helmet that Mike Ditka will not eat

1967: After a rash of head injuries, the NHL increases required helmet thickness from 3/8 of an inch to 3/9 of an inch

1968: John Olerud born wearing batting helmet

1975: In a setback for safety in sports, Evel Knievel successfully campaigns in favor of injuries in general

1992: The NFL breathes a sigh of relief as it is discovered that Dennis Byrd of the New York Jets is paralyzed not by a preventable head injury but by a completely unpreventable spinal injury

1996: Baseball cringes as signs of head trauma become obvious in one of its star players when Atlanta Braves outfielder David Justice divorces Halle Berry

2001: Plagued by terrible ratings and low attendance, the XFL tries to figure out how to give more players concussions

2005: Following the tragic death of Dale Earnhardt, NASCAR mandates the use of full-face helmets after studies show they offer more advertising space