Real Madrid fitness coach Antonio Pintus has recalled working with Luka Modric.
Modric, 40, has hit the ground running at AC Milan after making the move from Real over the summer.
"I don't think there is a real secret, but rather a combination of factors,: Pintus tells La Gazzetta dello Sport.
"Luka has an outstanding level of professionalism: he is careful with his training, diet, recovery, and above all, he has a mentality that drives him never to settle. He is a rare example of sporting long-termism, the result of daily commitment."
Pintus believes that Modric's way of thinking is the main characteristic.
"The difference between a great master and a master often lies in the mentality," he says.
"Modric has a desire to work and an endless hunger for victory. This, even more than his physique, is the driving force behind his long-term perspective."