Unai Emery and Aaron Ramsey disagreed over the playe's best role in the team, as he prepares to leave Arsenal for Juventus on a free transfer.
The 28-year-old has reportedly agreed a deal with the Serie A champions, that will make him the second highest paid player in Turin, behind only Cristiano Ronaldo.
However, Emery will not be particularly sad to see Ramsey go, with BBC Sport reporting that the Spaniard had reservations over his role in the squad and suitability to his football.
When Emery first arrived in North London, it was suggested that he would build the team around Ramsey, in an effort to convince him to sign a new contract.
But the former PSG boss eventually realised that Ramsey did not fit his style of play or formation, with the midfielder making it clear that he wanted to play as a roaming number eight, running onto the ball high up the pitch.
However, Emery does not use a number eight, with Ramsey restricted to play a deeper, more disciplined role without the license to roam or as a No.10, which he is not suited to.
It is why a move to Juventus has appealed to him so much, with Massimiliano Allegri generally using a three-man midfield, which will allow Ramsey to play the role he craves.