Mark Hughes has warned Stoke's under-performing players they risk ruining their season if they allow their poor run to continue.
Sunday's 4-1 defeat at Crystal Palace was their fourth loss in five Premier League fixtures and left them with a total of one point, three goals scored and 14 conceded.
The pressure is building on the manager after another promising summer transfer window. He had targeted an improvement on the ninth-placed finishes they have secured for the past three years, but is concerned doing so will soon prove beyond them.
"We have ambitions this season and, if this run continues any longer, we won't be able to achieve them," said Hughes, whose team were 2-0 down inside 11 minutes after goals from James Tomkins and Scott Dann.
"We need to turn this round very quickly. We haven't really got going yet.
"We've been ninth in the Premier League in the last three years, and we spoke about being better than that.
"We're giving ourselves too much to do. Confidence is damaged after the last few results, and you can see that in some of the players' play. A number of them are lacking form.
"Collectively we need to be better. We can't keep conceding easy goals like the first two."
With two further goals in the second half from James McArthur and Andros Townsend - Marko Arnautovic responded in the fourth minute of stoppage time for Stoke - Palace became the fourth team this season to score four past Hughes' team.
The absence of the injured Jack Butland has contributed much to the uncertainty seen in the defence playing in front of Shay Given, and Hughes said: "Jack's a loss for us, something we were not expecting.
"Last year it hurt us (when he was injured). We go with what we've got, and we have to be better. We have an opportunity on Wednesday (against Hull) and Saturday (against West Brom) to turn things round very quickly."
The result secured back-to-back victories for Palace for the first time since December 2015, when Stoke were again their opposition.
Since then they have been largely inconsistent, leading to sections of the crowd to question Alan Pardew, but Sunday's game concluded with them again chanting their manager's name.
Palace's supporters also aimed chants at Hughes of 'You're getting sacked in the morning', and Pardew could be seen waving his hand to ask them to stop. He believes, however, Hughes would arrest Stoke's slide.
"This is an experienced manager with very, very good players," Pardew said. "The media spotlight turns on to the manager when the results aren't good.
"Mark will deal with that. I have no concerns for him because he's terrific. He's having a bit of down time, but he'll be fine. I have heard those chants against me. I don't think it's right.
"(My) team knew what they were doing today. Our passing options, the shape of the team, the power of the team...
"Now we have to look to consistency. If we can have that level of performance again, we'll have a good season."