1965 NFL season

Prior to the season, both the NFL's Chicago Bears and the AFL's Kansas City Chiefs selected running back Gale Sayers in their respective league drafts.

This war between the AFL and the NFL would escalate until just before the 1966 season, when they would agree to merge and create a new AFL-NFL World Championship Game between the winners of the two leagues, that later would be known as the Super Bowl.

In the Western Division race, Green Bay won its first six games before a 31–10 loss at Chicago on Halloween put it in a tie with the Baltimore Colts.

Both teams won their next two games, but in Week Eleven, the Packers lost 21–10 to the Rams, and the Colts averted a loss by tying the Lions, 24–24.

In Week Twelve, Green Bay closed the gap with a 24–19 win over the Vikings, while the Colts fell to Chicago, losing the game (13–0) and their star quarterback, Johnny Unitas, to a knee injury.

With backup Gary Cuozzo passing for the Colts, they met the Packers again, in Baltimore, on December 12, and Paul Hornung scored five touchdowns as Green Bay won, 42–27, to take a half-game division lead, 10–3 to 9–3–1.

The following week at Lambeau, Starr returned as starter, with the Packers defeating the Cleveland Browns in the NFL Championship Game, the last before the Super Bowl era.