The Buffalo Bills were fresh off their second consecutive AFL Championship when head coach Lou Saban resigned to take the top job at the University of Maryland. The Bills didn't look very far to replace him, as they promoted their 33-year-old defensive coordinator Joe Collier on this date in 1966.
Collier joined the Bills in 1962 when Saban was hired. Collier was well-respected when he took over, having led the Bills' defense to top defensive rankings in the previous four seasons. Collier was as surprised to learn of Saban's resignation as he was to be offered the job. (Saban, for those keeping track, was back in the AFL coaching the Denver Broncos after just one season as a Terp.)
Unfortunately, Buffalo was beginning to age on the field. Pete Gogolak signed as a free agent with the NFL's New York Giants, and the other AFL teams were beginning to stockpile talent to challenge the mighty Bills. Adding to the hurt was the addition of the Miami Dolphins to the AFL. In the expansion draft, the Dolphins plucked RB Billy Joe from the roster, the man who was the main piece sent to the Bills in the Cookie Gilchrist trade a year earlier.
The 9-4-1 Bills went to the AFL Championship game for a third consecutive season in 1966, but the Kansas City Chiefs trounced them 31-7 and earned the right to play in the first Super Bowl. With stars retiring (Elbert Dubenion), getting hurt (Jack Kemp), and getting old, the wheels came off in 1967 and Buffalo went 4-10. Collier was still brought back for the 1968 season.
That year, Collier's team started the season 0-2 before Bills owner Ralph Wilson pulled the plug on Collier. Overall, he compiled a 13-16-1 record as the head coach of the Buffalo Bills. He was never a head coach again.
Following his stint in Buffalo, Saban hired him in Denver to be his defensive coordinator again. Collier led the Broncos' "Orange Crush" defense in the 1970s, and was kept on as defensive coordinator in the mile high city for 21 seasons. He was fired in 1988 by Dan Reeves, and finished his career as defensive coordinator in New England from 1991-1992.
It's interesting to note that Collier was drafted by the Giants in 1954, but declined to become an assistant coach at West Illinois University after a stint in the Army.