Michael Carrick and Kieran McKenna were keen for Manchester United to adopt a different style of play that was vetoed by former manager Ole Gunnar Solskjaer.
Caretaker manager Carrick and first-team coach McKenna wanted United to play with a back three sooner and arrest their porous defending.
Solskjaer had intended to change to a 4-3-3 formation in pre-season but United remained in a 4-2-3-1 until the 5-0 drubbing by Liverpool prompted a temporary switch to a back three against Tottenham, Atalanta and Manchester City.
United beat Tottenham 3-0 in the formation but abandoned it before half-time at Atalanta due to injury to Raphael Varane and changed to a back four for the second-half against City as they were 2-0 down.
Read more on manchestereveningnews.co.uk