1970: Cincinnati Bengals
The Bengals opened the 1970 season with a win over the Oakland Raiders but then proceeded to lose five games in a row. But they dominated the Buffalo Bills in Week 8 and that got them back on the right track as they closed the regular season by winning seven games in a row.
That gave them the AFC Central division championship and a trip to the postseason. In those days, teams played just 14 regular-season games and only four teams made the playoffs.
The Bengals were shut out by the Baltimore Colts in the divisional round of the playoffs, 17-0, but they had accomplished quite the feat after such a horrid start.
They were the first team to do this and it would be 45 years before another team matched it.