Rocky Bleier was the second back in the backfield.
Backfield Play - 1931 was released on: USA: 1 September 1931
Backfield Strategy - 1932 was released on: USA: 18 April 1932
Backfield in Motion - 1991 TV is rated/received certificates of: Iceland:L
Backfield in Motion - 1991 TV was released on: USA: 13 November 1991
Dick "Nighttrain" Lane, Yale Lary, Dick LeBeau, Dan Lewis??
The maximum is three (3).
O.J. Simpson and Wayne Patrick were the starting backfield for the Bills in 1970 along with Dennis Shaw at quarterback.
"Backfield in Motion"
Usually Reggie Brooks.
The starting backfield for the 1969 Buffalo Bills: Quarterback - Jack Kemp Half Back/Running Back - OJ Simpson Full Back - Wayne Patrick