Louis van Gaal expressed his amazement with the way his side played in the first half of Manchester United's 3-0 loss at Arsenal on Sunday.
Arsenal comprehensively defeated the Old Trafford club on the strength of two Alexis Sanchez goals and a Mesut Ozil tally that came during a blistering 19-minute stretch to open the match.
Van Gaal, whose men entered the weekend atop the Premier League standings, was taken aback by the shocking performance of his team, and expressed his astonishment after the match.
"I didn't expect that. I was surprised. No performing our gameplan, no will to win," Van Gaal said.
"We were top of the league so I was surprised -- maybe 'amazed' is a better word. When you give a team like Arsenal so much space to play football, you know you shall lose.
"We have prepared ourselves in that way, to play more compact but not to lose our aggression. It was amazing for me and very disappointing."
For Van Gaal, the baffling performance was one unbefitting of a league-leader, adding: "I don't know why it turned out like that. Normally I say things how I see them in the game. The players are in an emotional moment because we have lost."
"We have lost in a way you cannot lose when you are top of the league. You cannot start like that. The worst thing is everyone is flying away [for internationals]. So I cannot build a new situation to build up confidence."