The National Football League (NFL) did away with the chain gang – the team of officials who, with a literal chain, measure out ten-yard gains for the team on offense – for its Hall of Fame game on July 31 in Ohio. The only thing measuring first downs that day, as referee Shawn Smith told the New York Post, was Sony’s Hawk-Eye, consisting of six 8K cameras plus a hook-up to instant replay and another to the NFL’s Art McNally GameDay Central Officiating Center (AMGC), in New York. We first reported on the system a year ago.
“As on-field officials are notified of the measurement outcome,” says the NFL, “virtual recreations of measurements are produced in real time for the in-stadium and broadcast audience. The full operational process takes around 30 seconds, saving up to 40 seconds from a measurement with the chains.” In regular season games, however, “the chain crew will remain on the field in a secondary capacity.”
As of the 2025 season Hawk-Eye will be the “primary method for measuring the line to gain,” the NFL announced on April 1. It will serve at all 30 of the league’s stadiums and at any venue abroad hosting a game.
The system is also in use for professional tennis, cricket and rugby.
