Marcus Rashford scored the only goal of the game as Leicester slumped to a fifth match without a victory in all competitions.
The shock FA Cup defeat against League Two Newport County after losing to Manchester City in the Carabao Cup quarter-final has put pressure on Puel to improve Leicester’s ninth-place finish and 47 points from last season.
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Chilwell, who is a key part of the talented squad, has urged the Foxes faithful to trust Puel and the decisions he makes.
"Of course, him, us, everyone at the training ground are all trying our best. It would be nice if they were patient with us but you can understand they expect results with the quality we've got," said the England left-back.
"It's a learning curve for us and we are learning and improving. That's the main thing you have to take from the past few weeks.
"If you look at the team now from the team which won the league it's pretty much a different 11 and it's a very young squad.
"The fans expect results which is understandable but it's a young team which is learning. We're not scrapping in a relegation battle."
Sunday’s defeat was Leicester’s third straight loss at home and Puel says his side must start better to turn things around.
“My only concern is this game and to analyse this game as there's a lot of frustration.
"There was the possibility to make at minimum a draw but after our start it is too difficult to change the game.
"When you concede an early goal it is then difficult to change the game and get back," said Puel. "I don't understand, it is crazy because we make it difficult for ourselves.
"It is a shame because afterwards we played well as a team and with good intentions and caused United problems. It is crazy, but we will see what we can do. We need to take more responsibility."
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