Van Gaal began life as United coach in the best way possible on Wednesday night.
Wayne Rooney, Ashley Young and debutant Reece James all scored twice, and Danny Welbeck also found the net as United crushed the Galaxy in the Pasadena Rose Bowl.
Although he did not get on the score sheet, Herrera was United's best player on the night
The 24-year-old, who moved to Old Trafford in a £28million transfer earlier this summer, worked tirelessly from box to box, breaking up attacks and creating openings with incisive passes.
Herrera has only been working with his new manager for a week, but he knows Van Gaal well enough to realise he will not let the drubbing get to his players' heads.
"We are happy with the result but let's not forget this is a friendly and we still have many things to improve on," said Herrera, who was voted man of the match for his performance in California.
"Our coach is a very demanding coach, he always looks for only perfection and for that reason he is ideal for a club that always looks to achieve the greatest things, he won't let us sit back and relax, we still have a lot to prove."
United tried to sign Herrera last summer, but the transfer fell through.
Now the Spaniard is happy to be playing for a club he has watched and admired since he was young.
Herrera, speaking in an MUTV interview before kick-off, revealed United icon Eric Cantona was one of his own childhood heroes.
"I liked his character, he was a winner and always worked hard, he never lost one ball and was always thinking about the victory," the midfielder said of the Frenchman, who won four titles in five years at Old Trafford.
"This group of players (at United) has those same characteristics
We always want to win, we want to play well for the Man United supporters and Eric Cantona had those characteristics
Of course, he had personality too."
Herrera's performance drew praise from compatriot Juan Mata, who also excelled in the 3-5-2 formation deployed by Van Gaal.
United's club-record signing expects big things from Herrera, who he knows well from their time together with the Spain Under-21 squad.
"He is a great player and he showed that in the match," the former Chelsea midfielder said.
"I have known about him for a while from our days with the Spanish national youth teams and he was very good against the Galaxy.
"I am very happy for him
We have a good connection on and off the pitch.
"He can bring great things for us this year."
Mata's January move from Chelsea failed to stop United slipping to a seventh-place finish last season under David Moyes.
The Spaniard is aiming for a much higher position this term.
"Since I was a kid this club was trying to win the Premier league and so we will try to do that this year," Mata said.
United flew to Denver on Thursday afternoon to begin preparations for their first game in the International Champions Cup against Roma.
After playing the Italian giants, who have Ashley Cole in their squad, United will travel to Washington DC and Michigan to face Inter Milan and Real Madrid respectively.
If they top their group, United will contest the final in Miami on August 4.
Source : PA
Source: PA