The Dutchman, currently in charge of the Netherlands squad in Brazil, will take over at Old Trafford for the new season after the World Cup's conclusion amd assess his squad during pre-season.
Keane will be amongst those players after enjoying loan spells in the Championship with Leicester City, Derby County and Blackburn Rovers in the last two seasons before earning a place on the United bench under Ryan Giggs in the Reds’ final home match of last season against Hull City.
And the 21-year-old is now eager to make a mark under his new boss, aware that Van Gaal has never been shy to promote young players at previous clubs such as Ajax, Barcelona and Bayern Munich.
"I’ve heard the new manager likes to bring young players through and that’s always been the way at United," said Keane.
"Obviously with Giggsy staying on as his assistant that can only benefit the young players and hopefully we can get a good pre-season and a chance to prove ourselves."
Stockport-born Keane has been with United along with twin brother Will since his early teens and was part of the team which lifted The FA Youth Cup in 2011.
So he has grown up and learnt his trade alongside some of the best players in the world, with the likes of Rio Ferdinand and Ryan Giggs helping him in particular.
“I’ve heard the new manager likes to bring young players through.”
"When I was young I always had Rio Ferdinand on my back or t-shirts with Rio Ferdinand on," he revealed.
"Obviously when he first joined United he was my idol then and he still is. Luckily I managed to train with him for a few years. He’s had a big influence on me.
"He spoke to everyone and always gives you advice. If you make a mistake in a game, he’ll ring you and say what you should do better.
"He’ll text you or next time he sees you, he’ll give you a bit of feedback and I now see him as a friend so I know I can go to him anytime I want advice.
"And Giggs is an idol for every player that comes really, you see how professional he is.
"His enthusiasm for training every day, no matter that he’s been here for 20-25 years at the top level, means he comes in every day wanting to give his best.
"He’s always doing extra, whether that be yoga or passing and finishing. He’s just someone you can always go to for advice as well."
With Giggs having now announced his retirement from playing and forming part of Van Gaal’s new staff at Old Trafford, Keane believes his former squad-mate has all the attributes to be a successful coach.
And with the United legend already showing his faith in the club’s younger players at the end of last season, Keane is hoping that can help his own prospects.
"Over the last couple of years I think he’s, not kept a distance from the players, but maybe not been as involved as he was when he was younger because he could see himself going into that managerial role," revealed Keane.
"And I think he adapted really well in those last few games of last season. He looked the part and all the players were playing for him, which is the main thing really - they all wanted him to do well and everyone wanted to do their best for him.
"It’s great to still have him around but obviously sad that he won’t be playing anymore.
"He gave an inspirational team talk [at half-time against Hull]. I was a bit taken back by how good it was. It was a really good talk so you can tell he’s got it in him to be a world class manager."
Keane has been a regular for Gareth Southgate’s England Under-21 team over their Euro campaign so far, helping them top their qualifying table in the quest to reach next summer’s Finals in Czech Republic.
With the remaining two fixtures in Lithuania and Moldova coming up in September and then the prospect of the play-offs in October, Keane wants to remain in contention.
So if that means potentially heading out on loan again, it’s something which he accepts might be a possibility after learning so much in his previous spells away.
"It’s a good way to show how good you are and show what you can do," he added.
"When you first go into the Championship, in your first couple of games you are a bit taken back by how physical it is, especially as a centre half.
"I remember I made my Leicester debut against Kevin Davies and didn’t win a header against him.
"But after a couple of games you get used to it and you improve after every game."