1995 - The Jets try to improve Boomer Esiason's recovery time from a concussion by employing what the Times calls a "innovative but unproved form of biofeedback therapy." The Jets team physician explains the treatment as "having a head filled with marbles knocked around after a hit. The biofeedback is trying to put them back in the same order." The Jets team physician admits that they have no controls to show whether the treatment is effective. The Jets team physician is Elliot Pellman.

1997 - The American Academy of Neurology establishes guidelines for concussed athletes returning to play. The guidelines recommend holding athletes who suffer a Grade 3 concussion (loss of consciousness) be taken "withheld from play until asymptomatic for 1 week at rest and with exertion."

2000 - The NFL rejects these guidelines. ''We don't know whether being knocked out briefly is any more dangerous than having amnesia and not being knocked out,'' says neurologist Mark R. Lovell. ''We see people all the time that get knocked out briefly and have no symptoms,'' he added. ''Others get elbowed, go back to the bench and say, 'Where am I?' ''

Lovell is a consultant for NFL and the NHL.

2002 - Hall of Fame Pittsburgh Steeler center Mike Webster dies. Towards the end of his life Webster was living out a pick-up truck, using a Taser to ease back pain, and applying Super Glue to his teeth.

2003 - In a game against the New York Giants, Kurt Warner suffers a concussion. Confusion ensues over the medical chain of command. Warner's coach, Mike Martz, says that the team doctor cleared Warner to play. The doctor, Bernard T. Garfinkel, agrees. But asked why Warner was allowed to play even though he "had trouble deciphering plays," Garfinkel says, "That's a coaching decision, not a medical decision."

Warner leaves Giant stadium in an ambulance.

"I would say it's not the coach; it's ultimately the physician's decision," says Pellman. "But you can't have a hard and fast protocol, because the injury is all over the place."

2003 - Wayne Chrebet suffers a concussion in a November game against the Giants. The following discussion between Pellman and Chrebet takes place:

"There's going to be some controversy about you going back to play." Elliot Pellman looks Wayne Chrebet in the eye in the fourth quarter of a tight game, Jets vs. Giants on Nov. 2, 2003, at the Meadowlands. A knee to the back of the head knocked Chrebet stone-cold unconscious a quarter earlier, and now the Jets' team doctor is putting the wideout through a series of mental tests. Pellman knows Chrebet has suffered a concussion, but the player is performing adequately on standard memory exercises. "This is very important for you," the portly physician tells the local hero, as was later reported in the New York Daily News. "This is very important for your career." Then he asks, "Are you okay?" When Chrebet replies, "I'm fine," Pellman sends him back in.

2004 - In September, former Steelers offensive linemen Justin Strzelczyk leads the police on a high speed chase through central New York, colliding at 90 MPH with a tractor trailer. The trailer explodes, killing Strzelcyzyk instantly.