It was bound to happen at some point, but Manchester United suffered their first defeat of the season against Huddersfield on Saturday, losing 2-1 at Kirklees Stadium.
Goals from Aaron Mooy and Laurent Depoitre in the 28th and 33rd minute respectively gave the Terriers a shock 2-0 lead heading into half-time.
Marcus Rashford then brought his side back into the game with 12 minutes remaining, but United were unable to make up the deficit and left with nothing.
It was ultimately a 23rd-minute substitution that caused United's downfall, when Jose Mourinho replaced Ashley Young with Victor Lindelof.
Mourinho has previously said Lindelof still isn't ready to start a Premier League game and that much was evident against Huddersfield.
The £30 million summer signing was partly at fault for Mooy's opener but completely to blame when Depoitre was sent clean through on goal by a goal kick.
Instead of heading the ball clear, Lindelof ducked and allowed Depoitre to round David de Gea for an easy finish.
It was a poor performance from United on the whole, though, which incensed Jose Mourinho in his post-match interview.
The Portuguese didn't hold back in slamming his players for losing to Huddersfield and said something that came as a "big shock" to Gary Neville.
Neville, speaking on his Sky Sports podcast, said he was "stunned" by Mourinho's comments about the attitude of his players and how he'd never seen them so unmotivated for a game.
Jose Mourinho: "I don't even remember a friendly match where our attitude was so poor. When I lose matches, I like to lose because the opponent was better and had more quality.
"But when you lose because of attitude, that is really bad. I heard Ander Herrera in his flash [television] interview saying the attitude and desire was poor.
"Oh my God, when a player says that, or a player feels that, I think they should all go to the press conference and explain why - because I cannot explain that."
Gary Neville: "I thought the atmosphere [at Huddersfield] would be tough for United but I thought they would come through it.
"I'm stunned by the result and stunned by Jose Mourinho's comments after about the application of the players, that it was the worst he had seen them up for a game. I'm really surprised.
"It was a big shock for me. The anxiety runs not just through the team but also into the crowd, and if you're away from home, you have to cut those things out."
Neville is clearly worried by what he saw and heard on Saturday and will only hope United have the character to get back to winning ways.