The Jets improved steadily on the field after Joe Namath's arrival. In 1967, the former Alabama quarterback led the Jets to an 8–5–1 record, their best record yet. Namath reached a milestone by passing for 4,007 yards in 1967, a 14-game season, making him the first-ever professional quarterback to pass for 4,000 yards in a season. This was especially remarkable considering that at the time, 3,000 yards passing was considered an excellent year.
In 1968, the Jets would reach the pinnacle of their existence and provide the moment that would indicate the AFL's coming of age. Under Namath's guidance, the Jets rose to the top of the AFL, defeating the Oakland Raiders in a thrilling AFL Championship Game, 27–23, on December 29. The win qualified them to represent their league in a game that was being referred to for the first time as the Super Bowl (and referred to retroactively as Super Bowl III) on January 12, 1969. They were pitted against the champions of the NFL, the Baltimore Colts. At the time, the AFL was considered to be inferior to the NFL, and most people considered the Jets to be considerable underdogs and treated the Jets as such. That would change three nights before the game while Namath was being honored by the Miami Touchdown Club as its Player of the Year. Namath took exception to a heckling Colts fan and used that moment to lament the lack of respect his team had gotten to that point. He then said "We're gonna win the game. I guarantee you." His audacious remark proved correct, as the Jets created one of the greatest upsets in football history by defeating the Colts 16–7. This victory showed that the AFL was capable of competing with the NFL. It also gave Shea Stadium the first of two World Championships teams in the 1969 calendar year , as the New York Mets won the World Series nine months later.
In the 1969 season, the Jets won a second consecutive Eastern Division title with a record of 10 wins and 4 losses. In the playoffs, they lost to the Kansas City Chiefs, 13-6, at Shea Stadium on December 20.
Namath's career mirrored the Jets after the AFL-NFL merger became final in 1970. He missed much of the 1970, 1971, and 1973 seasons due to injuries, most notably to his ravaged knees, which robbed him of his mobility and much of his effectiveness. He would not throw more touchdowns than interceptions in a season after the merger, and in fact only had two post-merger seasons (1972 and 1974) where his performance could have been classified as reasonably successful (the Jets also had relative success in those years as well, finishing 7–7 both years). After a terrible 1976 season in which Namath only threw 4 touchdown passes against 16 interceptions (six of them in a 38–24 loss to the New England Patriots) in 11 games, Namath was waived by the Jets when a trade couldn't be worked out to facilitate his move to the Los Angeles Rams. He would play only four games for the Rams before announcing his retirement at the end of the season, at the relatively young age of 34. Although Namath would make the Hall of Fame, it was widely acknowledged that he made it on his performance through the 1969 season and his role in leading the Jets to a victory in Super Bowl III.
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