Ken Anderson is one of the greatest quarterbacks in football history. Wikipedia cites his legacy as follows:
At the time of Anderson's retirement following the 1986 season, he held NFL records for consecutive pass completions (20), completion percentage for a single game (20 of 22, 90.9%, vs. Pittsburgh in 1974) and completion percentage for a season (70.6% in 1982), as well as the Super Bowl records for completion percentage (73.5%) (since broken by Phil Simms) and completions (25; Tom Brady and Drew Brees each hold the current record with 32). Anderson was ranked 6th all-time for passing yards in a career at the time of his retirement. His record for completion percentage in a season stood for 27 years after his retirement (broken by Drew Brees in 2009).
As of 2005, Anderson was among the top 30 all-time leaders in pass attempts (24th), completions (18th), passing yards (21st) and passing touchdowns (28th). He led the NFL in passing yards and completions twice and led the league in fewest interceptions per pass attempt on three occasions. He ranks fourth in NFL history for postseason quarterback rating, 93.5. He also holds the record for highest career completion percentage in the postseason at 66.3%.
Throughout his career Anderson was noted for never taking credit for a win, instead giving all the praise to his teammates. Normally after he had a big game he praised his offensive line, despite statistically having one of the worst offensive lines in NFL history (he was sacked 398 times at the time of his retirement, the most of any quarterback). Anderson played in a west coast offense at a time when running a precision offense was difficult because of the rules that were in place at the time. From 1980 until his retirement under a more liberalized passing game Anderson completed 64.1% percent of his passes while the league average throughout the 1980s was 55.5% and would be the modern equivalent of a passer completing 68.4% percent of his passes on average.
He has been nominated for the Pro Football Hall of Fame several times, and on two occasions was among the 15 finalists for enshrinement (1996 and 1998), but has not yet been voted in. In 2008, NFL Network selected Anderson as #10 on its list of top 10 players who have not yet made it into the hall of fame.
In May, 2011, statistics site Cold Hard Football Facts presented a lengthy argument supporting Anderson's candidacy to the Pro Football Hall of Fame.
Anderson and his first-round opponent played in the league during the same four year period from 1983 through 1986 (though Anderson played sparingly in 1985 and 1986). Anderson's QB ratings in those four years were 85.6, 81.0, 86.7, and 51.2. (In his last year he threw only 23 passes). His first-round opponent's ratings were 54.9, 76.8, 70.2, and 79.0.
Anderson's career QB rating is 81.9, despite playing his early career in the days before the liberalized pass blocking rules and passing rules. Anderson also reported as a rookie to a team that was only three years from expansion. His first-round opponent's career QB rating is a dismal 79.9, despite playing his entire career under the new easy passing rules and despite being allowed to play for a playoff-caliber team his entire career.