The 62-year-old Red Devils manager started working with his new United squad following the World Cup after penning a three-year deal in May.
He is very honest, straight, speaks with everyone to his face. I think this is good, a perfect way to do it, saying what you think about the players in front of them
Mata was ousted from Chelsea by Jose Mourinho after the Portuguese manager deemed the Spain international surplus to requirements.
And the 25-year-old, who moved to Old Trafford in a £37.1m deal in January, likes that Van Gaal is willing to speak his mind directly to the players.
“He is very good on and off the pitch. He is a good man and a great manager,” Mata is quoted as saying by Manchester Evening News.
“He has a lot of experience, he has won trophies in previous teams too, so it’s a good chance for me to learn from him and for us to improve as a team.
“He is demanding. He is very honest, straight, speaks with everyone to his face. I think this is good, a perfect way to do it, saying what you think about the players in front of them.”
Mata has scored six goals and made four assists in 15 Premier League appearances following his move to United.
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