On this day, September 9th in 1969, the Washington Redskins lost the top pass catcher in the NFL when Bobby Mitchell decided to retire at the age of 34.
“I couldn’t stand being on the team and being on the bench,” Mitchell offered at a news conference at the time.
Despite being the top active receiver in the NFL in 1969 with 521 catches (7053 yards), he had been reduced to a reserve role (Washington had a fleet of young receivers), and was already planning on retiring at season’s end.
When he retired, Mitchell sat behind only Raymond Berry in passes caught, and only Jim Brown in total yardage (14,078).
http://archives.chicagotribune.com/1969/09/09/page/60/article/point-of-view-janeway