Marcelo Bielsa is one of world football's most fascinating coaches, and he is not afraid of picking up his ball at taking it home when he is not happy.
Leeds United are trying to land him as their next manager [SkySports] and they will need to work closely with Bielsa and deliver what he wants.
The strong-willed Argentine proved he is not a man of idle threats during his short lived spell at Lazio, when he quit the club after just two official days in charge.
Bielsa's comments following his exit should act as a warning to Leeds not to undercut him.
He left Lazio because he expressly told the club to sign players in time for pre-season... and they did not deliver.
Bielsa was quoted by Goal: "After four weeks working together with you, we could not sign any of the seven additions in the work program expressly approved by the President Claudio Lotito.
"It was agreed as essential to the implementation of the work program that we would sign at least four footballers before July 5, with the objective that they would be able to participate in pre-season.
"For my style of work we needed to have these players arrive in a timely manner to train."
This was only in 2016, and if there are lessons to be taken from this for Leeds United.
Succintly, make rapid progress with Bielsa's approved transfer targets and do not let him down.
Fans can also expect deals to be done sooner rather than later, as Bielsa would prefer to have his core group to coach when pre-season begins.
This puts serious pressure on technical director Victor Orta and owner Andrea Radrizzani to negotiate and seal transfers quickly.
Perhaps they can get off to a flying start by landing heavily linked free agent Abel Hernandez.