 Collier served under Brown from 1946 to 1953 , a period in which the team won all four titles in the AAFC before moving to the National Football League ( NFL ) in 1950 . That season the Browns captured the NFL title and then reached but lost the following three championship games . Collier 's coaching style was the opposite of Brown 's ; Brown was a disciplinarian whose stern nature and aloofness often brought him into conflict with players , while Collier was a friendly , warm man whose patience and studiousness endeared him to players . " Everything had to be perfect ; he was a stickler on perfection – but at the same time , he had great patience , " Browns quarterback Otto Graham said in 2007 . After the 1946 season , Brown asked Collier to analyze every play run by the offense , and Collier came up with a detailed breakdown of why each play succeeded or failed . This was the genesis of an annual grading system Collier developed to evaluate players ' performance . The Browns used it for many years . 
