When the AFL and NFL merged in 1970, the Buffalo Bills moved from the five-team AFL East to the five-team AFC East. It took them ten years, but on this date in 1980, the Bills clinched their first AFC East title.
The last time the Bills had won their division was 1966, and they hadn't made the post-season since 1974. Chuck Knox arrived in 1978, however, and a team that won three games in 1977 improved in each of Knox's first three seasons, culminating in an 11-win season in 1980 and the team's first division title in the NFL.
After a loss to the New England Patriots in Week 15, the Bills needed a win in their final game to secure the division crown - and a loss would have eliminated them from the playoffs entirely. The Bills traveled to the 6-9 San Fransisco 49ers, led by their quarterback Joe Montana, who took over for Steve DeBerg midway through the year.
After a Joe Ferguson touchdown pass to Jerry Butler, the Bills missed the extra point. Fortunately, it didn't cost them much, as San Fransisco missed the extra point following their first quarter touchdown. A Curtis Brown rushing TD and successful PAT put the Bills up seven at the half. Montana tied it up with a TD pass in the third quarter before a field goal and safety by the Bills capped the scoring at 18-13.
Joe Cribbs, who had established himself as a premier back during the season, ran for 128 yards on 18 carries, including a 48-yard scamper. The Bills were out-gained 298 to 267, and lost the turnover battle. Ferguson was 12 of 20 for only 102 yards in the game.
The Bills traveled back to California in January to take on the 12-5 San Diego Chargers, led by Dan Fouts. Despite taking a 14-3 lead into halftime, they fell in their second NFL playoff run.