The midfielder had an underwhelming first season at United after last summer's move from Chelsea.
But Ten Hag says: “You can't judge (his first) season because he was injured. But when he is fit, he will be a very good player for us and we can use him. He’s versatile and you need that in a squad.
"You need certain types in the squad, like you need the leaders, you need the team players. You need individuals, multi-functional players. And yeah, definitely he is one of those players. He can play in several positions and I'm sure he will help the team.”
On new coach Ruud van Nistelrooy helping Marcus Rashford, Ten Hag also said from LA: “That is a reason why he is here, but not only for the strikers. He is much more than this. But Rashford can only prove himself and he is capable of it. He has scored so many goals already at a relatively young age.
"So, he's capable of it. So I'm confident and 100% believe he can do the same as two years ago.”