Miralem Pjanic has praised Massimiliano Allegri for "making everything work in the best way" during his time in charge at Juventus.
Pjanic arrived from Roma two years into Allegri's reign but has been impressed by the way the Italian has continually pushed a star-studded squad to get better.
"We are a fantastic group and I have to congratulate our coach, who has always managed to make everything work in the best way," he said at a club event on Thursday at the Allianz Stadium.
"With him, we managed to win. In football you always have to work to improve, I have always had this mentality."
On the Portuguese superstar, Pjanic added: "His concentration levels have always been out of the ordinary, both when things are going well and also when that's not the case."
The Bosnia-Herzegovina international – who has been linked with a move to Paris Saint-Germain – also revealed he turned down the chance to represent France, having moved to the country as a teenager to join Metz.
"I left my country, Bosnia, very young because of the coming war. I lived in Luxembourg, a very small country, then I moved by myself to France, still young, to follow the dream of football," Pjanic explained.
"I am happy to have chosen to play for Bosnia even if I could have played for France instead. I was only 18 at the time and [France coach] Raymond Domenech called me to see what my plans were.
"I went to see a Bosnia-Denmark game when I was 13 and from that moment on, I knew I wanted to represent Bosnia."