The 19-year-old is one of the hottest prospects at Old Trafford after a breakthrough season last year.
In total, he made 34 appearances for the Red Devils, scoring and assisting five each.
But the teenager is hoping for even more exposure to first-team football next season while Ten Hag is a clear fan.
However, the Dutchman wants even more from Garnacho and has challenged him to force himself into making more starts, according to Manchester Evening News.
It is a similar sentiment that was echoed by Ten Hag last season after Garnacho came on and scored against Wolves in the Premier League.
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"Garna, we see it, the view, because he scored a great goal," Ten Hag said in May.
"He came on and he scored a goal. He did almost everything good and that will give him belief and that is good for the rest of the season.
"He is back, it will give him confidence and he can have an impact.
"One of the aspects for the biggest talent is that they are mature.
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"First, they take responsibility and second, they are mature.
"To bring in the skills, they have belief that they can dominate opponents. And once again he did it.
"He had a big impact in many games either when he's starting or coming on.
"He's ready, straight into the game and that is so important for the squad that you can bring young players and I'm happy you can bring young players.
"Hopefully, he can progress so quickly he can compete for a starting XI position because that is his next challenge.
Of the 34 appearances the youngster made last season, only 11 were starts while his pace and dynamism made him a useful weapon against tired legs.
But the Argentina international looked impressive against Real Madrid from the start, leaving Dani Carvajal and Lucas Vasquez in troubled situations on several occasions.
And he gave Kyle Walker plenty to think about in the FA Cup final last season against Manchester City and would have had an assist or two or another day.
However, Garnacho's toughest situation is the fact he prefers to play on the left-wing.
Currently, Marcus Rashford occupies that position and is the clear first-choice after scoring 30 goals last season.
Garnacho has started up front on occasion and also on the right-hand side.
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But with a new striker set to be signed this summer and Antony a key player under Ten Hag, finding joy in either position also looks a steep ask.
Nevertheless, at his young age, the former Atletico Madrid trainee still has plenty of time on his hands and more development to come.