The Red Bulls came back twice to level the scores at Red Bull Arena but were beaten by Justin Braun’s third goal to experience just their second defeat of the season.
Marquez admitted that the players went away from what they know best whilst star striker Thierry Henry said the midweek trip for a friendly with Montreal Impact certainly did not help.
“We didn't do our jobs," Marquez said. "And that kind of distraction cost us the game."
Henry added: "I still maintain that's now how you prepare [for a] game, with one training session before a game. You saw today that the team was a bit flat."