Wenger was denied a point on his final visit to Old Trafford as Arsenal manager by a late Marouane Fellaini goal, and the Frenchman admitted after the match that it is a steep learning curve for some of his players.
"It was a good performance. It reflects a little our away season," he told Sky Sports News. "We had chances and on the counter we did not use our opportunities as well as we could have.
"It was very positive for the young team, but it is very disappointing in the dressing room and I think in the last 20 minutes you can see that some of the players are not used to that pace and intensity.
"It is good to see them in this atmosphere - who can win challenges. You can know their level, but you see what they can produce. It was hard to name a bad performance in our side."
Arsenal are now officially unable to finish in the Premier League's top four, with fifth the best they can hope for.