BALTIMORE (AP) BALTIMORE (AP) - The hard-hitting, no-nonsense linebacker Mike Curtis has died at the age of 77. He died Monday in St. Petersburg, Florida. Son Clay says on Twitter his father died of "complications from CTE,” a degenerative brain disease. Curtis helped the Colts win a Super Bowl during a 14-year career spent predominantly in Baltimore. He earned the nickname “Mad Dog” because of his fierce play in the middle of a strong Baltimore defense.