Steve Bruce admits Wigan may have got "a bit above our station" and ordered them to go back to basics following the humiliating defeat by Aston Villa on Sunday.
The Latics enjoyed an unbeaten September but lost at home to Middlesbrough earlier this month and led twice at Anfield before losing to Liverpool.
The 4-0 defeat at home to Villa last weekend was their worst defeat of the season and Bruce said: "We've been punished and badly beaten and we'll have to work on it."
He added: "We played very well at Anfield and against Middlesbrough but the Premier League is very unforgiving.
"Maybe we're all getting a bit above our station and it's time to go back to basics and defend properly.
"You can't win a game in the Premier League when you defend like that.
"We haven't done our jobs defensively. That has been our strength because in the games that we've lost we have lost by the odd goal.
"We conceded three last week and four against Villa. Three of the four that we conceded against Villa were so poor defensively and the glaring mistakes were not acceptable at this level.
"If you do that against a really good Aston Villa side then you have your backsides kicked."
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