Franco Harris, the Hall of Fame running back who wrote "The Immaculate Reception," has died at 72.  

Image Source: Erik Williams-USA TODAY Sports

Image Source: Erik Williams-USA TODAY Sports

Dok, Harris' son, told the Associated Press that his father died in the wee hours of the morning. There was no information provided as to what caused death.

Image Source: Erik Williams-USA TODAY Sports

Two days before the 50th anniversary of the play that jolted the Steelers into the NFL's top, he passed away.

Image Source: Erik Williams-USA TODAY Sports

Just three days before a halftime ceremony will be held in Pittsburgh to retire his No. 32 before they play the Las Vegas Raiders.

Image Source: Erik Williams-USA TODAY Sports

Harris, a running back with the Pittsburgh Steelers in the 1970s, gained 12,120 yards and won four Super Bowls.

Image Source: Erik Williams-USA TODAY Sports

The dynasty began when Harris ran on Terry Bradshaw's last-second pass in a 1972 playoff game against Oakland.

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Harris, a 6-foot-2 and 230-pound workhorse from Penn State, discovered that he was in the middle of everything that was going on.

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Super Bowl IX was won by Pittsburgh, 16-6, and he rushed for a then-record 158 yards and a touchdown.

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In three out of the four Super Bowls that Franco Harris participated in, he was able to score at least once.

Image Source: Erik Williams-USA TODAY Sports

Nearly 40 years after his retirement, his record of 354 career yards rushing in the NFL's biggest game still stands.