Manager Steve McClaren acknowledged Newcastle were "close to a crisis" after a 1-0 League Cup home defeat by Sheffield Wednesday.
The Magpies have lost four games in a row and their only win under McClaren was against League Two side Northampton in the same competition.
McClaren said: "Is the job harder than I thought? Absolutely. Without a doubt.
"People say it's a crisis and it's getting very close to it. We deserve to be criticised."
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Lewis McGugan's shot from outside the box in the 76th minute gave the Owls victory on Wednesday.
The Championship side had made 10 changes from their previous match and the win earned them a home tie against Arsenal in the fourth round.
Newcastle, who have won only four matches this year, face champions Chelsea in the Premier League at 17:30 BST on Saturday.
|A far from awesome foursome|
|Newcastle have won four games in 2015. They beat Hull 3-0 on 31 January.||Newcastle picked up one point from their next 10 matches before beating West Ham on the final day of the season to stay up.|
|A 1-0 win at home to Aston Villa on 28 February lifted them into 11th place.||Steve McClaren's only win was in the League Cup at home to Northampton.|
Goalkeeper Tim Krul said: "Everybody needs to grow now. We need to come out and show we are real men."
"What we are doing at the moment is really not good enough."
McClaren has won only three games in his past 21 in charge of Newcastle and Derby County, but remains confident of changing his fortunes.
"The only people who can do anything about it are in that dressing room," he added. "We have to be fighters, not victims.
"How far do you go down before you turn it around? Do you say 'that's enough'? For me, that's enough.
"We need results. There is trepidation but it's a great game for us on Saturday."