Arsene Wenger was made to pay for playing a weakened Arsenal side against Southampton in the EFL Cup on Wednesday.
The likes of Carl Jenkinson, Rob Holding and Jeff Reine-Adelaide started for the Gunners, who slumped to a 2-0 defeat and offered very little in response.
Defensive errors cost Arsenal. Jenkinson was caught out of position for the first, where Ryan Bertrand had space down the left to cross to Jordan Clasie, who fired home.
And for the second, Jenkinson was once again the culprit as he gave away possession in a dangerous position, allowing Bertrand to squeeze his shot past Emiliano Martinez.
Wenger has since been criticised for deploying his second-string side, but it would seem he made an even bigger error of judgement before the game.
In a post-match interview, the Frenchman revealed how Mohamed Elneny - who was replaced by Granit Xhaka in the 43rd minute - was sick pre-game but played anyway.
"He was sick before the game. He decided he felt well enough," Wenger said.
"I could see after five or 10 minutes that he was not right. He has no medical injury problem, but he has diarrhea or a stomach problem."
As Arsenal manager, it's Wenger's responsibility to decide whether his players are fit to play, not the other way around.
It was a careless and costly mistake to allow Elneny to play. The Egyptian should have been rested to recover while Xhaka took his place in central midfield.
Wenger may well regret not playing a stronger team after admitting Aaron Ramsey and co. lacked match sharpness and fitness.
"It's down to us to give the fans what they want. It is a fact. We have to live with that," he said, per the Daily Mail.
"We had a disappointing performance, particularly in the first half. I think we were not good enough defensively and gave cheap goals away.
"It was better in the second, but it was one of those nights where you look like you could play two hours without scoring a goal. We didn't have enough urgency in the first half and were weak in some departments.
"We paid for that. We were not incisive enough in the first half especially. They played deeper in the second half and were sharper than us and fitter."
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