On the legs of running back O.J. Simpson, the Buffalo Bills set the NFL single-season record for most first downs on this date in 1975.
Playing in a 14-game season, the Bills accomplished the feat with a whole game left to play after amassing 26 against the New England Patriots. They finished with 318, a record for the 14-game season and an average of 22.7 per game. The current NFL record is 398, set by the 2004 Kansas City Chiefs and their potent offense.
The Bills managed 162 first downs on the ground and 132 through the air behind the best rushing attack in the entire NFL. The team scored the most points and gained the most yards in the league that year, but managed only an 8-6 record to finish seventh in the AFC. It is one of three times in team history where the offense was tops in the league, and the only time the Bills didn't win at least 12 games and an AFL/AFC Championship (1964, 1991).
Buffalo's defense was at or near the bottom of the league in virtually every defensive category that season, and gave up 30 or more points in half of the team's games, including five of the six losses.
Simpson made the All-Pro and Pro Bowl teams.