The Spaniard arrived at the club back in 2014 and spent two years under Louis van Gaal fluctuating between a variety of roles.
This season, however, has witnessed a monumental change in Herrera’s midfield approach, and he was duly awarded with the Sir Matt Busby Player of the Year award last month.
And Herrera, reflecting on his early discussions with Mourinho, noted that they agreed he needed to provide something different ahead of the 2016/17 campaign.
“I know it is difficult to play in a big club like Manchester United as a No 10 because you know how many goals you have to score to play there,” Herrera said.
“So I thought I had to add something to my game. I had to give more options to the manager. We both agreed.
“He told me that I was going to play sometimes a different role in the team. He told me sometimes I was going to play more defensive and in other games he was going to need me more forward. I told him I’d play wherever he wanted me to play and I would give my best.”
Tactically speaking, you could say that being used as a box-to-box player in a midfield trio, as opposed to playing No.10 one week and defensive midfield the next, has allowed Herrera to ease into a rhythm under Mourinho.
The most tangible change, however, has been the attitude shift: Herrera has developed a gritty, sometimes nasty edge this season, acting as United’s hired aggressor in the middle whilst Paul Pogba surges forward and Michael Carrick recycles the ball.
Their roles have helped, in turn, to shape the nature of the 27-year-old’s function as well, and supporters will desperately hope that last year was just the start of a period of midfield domination from somebody many believe should be the club’s next captain.