Sead Kolasinac is always looking to improve himself on the pitch.
The Bosnia & Herzegovina international has studied a whole host of players in his position ever since he started playing football as a young boy.
So who are the five left backs that he's modelled his game on?
"My No 1 is Roberto Carlos," Kolasinac said. "He was a dangerous left back and he played forward a lot too. He was probably the first left back who really stood out for me and has stuck in my mind.
"He started everyone shooting with the outside of boot. It's a strength that nobody has been able to re-create, except maybe Quaresma, but it's definitely something really special.
"After that, it's Ashley Cole, a powerful left back who gave his all in every game. When I started following the Premier League, he was just starting out and was one of the best there.
"The way he got stuck in for his team was really impressive and it's why he won so many titles throughout his career.
"My No 3 is Marcelo. I like him because of the way he controls the ball and I honestly think he could play in midfield or as a supporting striker because he handles the ball like an attacking player.
"He's technically strong, his crosses are really good and over the past few years, he's definitely been one of the best left backs in the world.
"Then Paolo Maldini is next. He was a real leader. His personality, the way he was with the team, that really impressed me at the time. He was such a driving force and really led his team by example.
"And then finally, my No 5 is David Alaba. He's played at a really high level over the past few years, in attack and defence, and is really effective with a lot of power. That sets him aside from the rest."