Former Barcelona manager Quique Setien reportedly told Lionel Messi once that he could leave the room if he didn't like what was being said.
According to Mundo Deportivo, Messi grew increasingly frustrated with Setien's tactics at the end of last season, and one such altercation is said to have left Messi disillusioned.
After Barcelona dropped points in a crucial La Liga fixture against Celta Vigo, Messi is said to have spoken up in the dressing room against Setien. It was one of a few results in a short space of time that left Barcelona unable to catch Real Madrid in the race for the La Liga title last season.
Messi reportedly told Setien to show more respect for the players in the dressing room, a lot of whom had won far more trophies than the manager had.
"If you don't like what I said, you know where the door is," Setien reportedly replied to Messi. The Argentine reportedly laughed it off then, but it was one of many things that left him disillusioned with the club.
In August, Messi asked to leave the club, and launched a tirade against President Josep Maria Bartomeu.
Lionel Messi's series of tiffs with the Barcelona hierarchy

Even though Barcelona didn't allow Messi to leave the club, stating that his option to unilaterally rescind his contract had elapsed in June, that didn't stop Messi from berating the club's board.
The Argentine had called the Barcelona board one without a sense of direction or a plan for the club. He said that the only reason that he didn't leave Barcelona in the summer was that he didn't want to take the club to court to fight a legal battle.
A few weeks after that, the board were again the target of Messi's wrath, when Luis Suarez was allowed to leave the club to join Atletico Madrid.
Messi said that Suarez deserved the send-off of a Barcelona legend, instead of what he got. He also added that with the people in charge of the club, nothing surprised him anymore.
Setien was sacked by Barcelona at the end of last season, which ended in ignominous fashion for Barcelona. After they lost the La Liga title to Real Madrid, they were embarrassed in the UEFA Champions League.
Bayern Munich thrashed Barcelona 8-2 in the quarterfinal, in what proved to be Setien's final game in charge of the Catalans.