Erik ten Hag accused Manchester United's players of "sleeping" in their disastrous start against Cadiz.
United were 2-0 down after 13 minutes through goals from Carlos Garcia and Anthony Lozano before Anthony Martial converted a penalty before half-time.
Ten Hag replaced all 10 outfield starters at half-time and Kobbie Mainoo equalised quickly but Cadiz eventually ran out 4-2 winners.
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United's starting defence included Aaron Wan-Bissaka, Teden Mengi and Brandon Williams - all starting under Ten Hag for the first time.
Williams conceded a free-kick Cadiz led from and Wan-Bissaka was a bystander for the second goal that came from his side.
"Quite clear, we were not awake," Ten Hag told MUTV. "Still sleeping. First 15 minutes. And we prepared - they are a threat in transition, we see the second goal, it can't happen, you are not awake. Bad defence but especially in the midfield we got run off, it's not possible, unacceptable.
"It's the first goal as well - the set-play - bad organisation, indisciplined organisation to concede the goal.
"But after that we came in again and a penalty, a clear one, maybe second-half we deserve another penalty because the first one was a clear one. We came into the game but couldn't make the equaliser in the first-half.
"We are unhappy with this game. Of course, you always have some positives when you lose a game, but today there are more negatives."
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