[2] He played college football for the California Golden Bears where he graduated with a major in history.
Hendrickson was a member of the San Francisco 49ers when they won their fourth Super Bowl XXIV on January 28, 1990.
He scored on a 1-yard run against the Kansas City Chiefs in a January 1993 playoff game in San Diego, to cap off a 17–0 shutout.
He suffered from many of the same symptoms as other former NFL players who have been diagnosed with trauma-related brain injuries resulting from concussions during their playing years.
The NFL pension plan's six-person board determined his injuries were "non-football related", which made him ineligible for enhanced benefits.