New Chelsea coach Thomas Tuchel showed the kind of ruthlessness he expects from his players when he hauled off Callum Hudson-Odoi.
Hudson-Odoi, who had replaced Tammy Abraham at the break, looked bewildered as he left the field to be replaced by Hakim Ziyech in the 76th minute of the Premier League match.
"We brought in Hudson, but with Hudson I was not happy with the energy and with the attitude and counter-pressing," Tuchel told BT Sport.
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"So, we decided to take him off again, because we demand a lot and we demand 100%.
"So, it's a decision for today, it's a hard decision I know for the players to come on and off. But tomorrow, latest tomorrow, it's forgotten and he has all possibilities to start again against Atletico," he said, referring to Tuesday's Champions League last-16 tie with the Spanish league leaders.
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Tuchel had a sometimes tense relationship with players - and senior officials - at his previous clubs, which include Borussia Dortmund and Paris St Germain.
On Saturday, he repeated his recent concerns that Chelsea - despite fielding strikers Timo Werner and Tammy Abraham - were not creating enough chances.
"After a match like this if you need a penalty to score once, it tells the story," Tuchel said.
"I want to watch this game once or twice to understand where we can help and where we can improve because it will not be easier to score against Atletico," he said ahead of the first away leg, which is being played in Bucharest.
The game has been switched due to Covid-19 restrictions in Spain that prevent Chelsea's players from entering the country.
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