The 23-year old San Diego native played a full 90 minutes in the 1-1 draw with Columbus Crew at Red Bull Arena on Sunday and Backe said it was an accomplished showing from the inexperienced former Austin Aztex youngster.
"I'm quite happy with Austin da Luz's performance,'' said Backe.
"Understandably, in the first half he played a little bit too simple when he could have attacked and gone forward. Overall, I expect that when you play your first game in the MLS; you play simple, play safe, and just try to get into the game. No pressure plays.
"I am happy. I wouldn't say surprised, but a little bit that he could do it for 90 minutes. It's such a difference to play reserve games than to play a competitive MLS game.''
And da Luz admits it was nice to be given an opportunity with a bunch of Red Bulls players away on international duty.
"I knew this opportunity would come with the gold cup and the guys away, so I've just been working hard and trying to mentally prepare for this opportunity,'' he told the NY Post.
"I feel like I took advantage of it Saturday night and hopefully I can keep doing that for as long as I need to.''