Following Raphinha’s return from injury, Rashford, 28, has some off the bench in four of his last five games across all competitions.
The Man United loanee has made an impressive start to his Barcelona career, scoring six goals and providing eight assists in his 21 games.
Speaking ahead of their La Liga game against Osasuna, Flick praised the England international for his ‘fantastic mentality.’
“When he’s on the bench, it shows also we have a good team,” Flick he told reporters.
”In this position we have excellent players. What I can say, he’s an absolute professional player. His attitude, mentality is great. In the beginning, he had to adapt a little bit, but now he’s on his best level.
”I speak with the players when they’re not playing, explaining why, and what he said to me the last day, was ‘Boss, you don’t have to tell me this, it’s only about the team. We have to win three points, nothing else is important.’
“It’s the right attitude. The mentality he has is fantastic and I am really happy he is here.”