Stoke boss Nathan Jones admitted his much-changed side were "nowhere good enough" after they crashed out of the Carabao Cup to League Two Crawley.
The Potters were knocked out 5-3 on penalties after the tie had finished 1-1 after 90 minutes.
Sam Vokes had given Stoke the lead midway through the first half, but Nathan Ferguson replied before the interval and Stoke were forced to play the final 30 minutes with 10 men after Nathan Collins received a straight red card.
Welshman Jones, under pressure after failing to win any of Stoke's opening eight league games, made 10 changes and said he took "full responsibility" for the defeat.
He said: "It was as bad a 45 minutes as I've had as a manager, and then the red card killed us.
"The first 45 minutes was lacklustre, there was no desire and a few lacked match sharpness.
"Crawley were good on the night, but I`m very disappointed with the first-half performance."
Asking if he was coming under increasing pressure, Jones replied: "As a Championship manager there is pressure all the time. It is no fun.
"We were nowhere good enough and I take full responsibility. What I'm hoping is that everyone does their job."
Crawley head coach Gabriele Cioffi praised his team's never-say-die attitude after they booked a place in the last 16 for the first time.
Italian Cioffi believes the whole club has been boosted by full houses against Norwich and Stoke, and stressed the importance of following up with another strong performance at home to Walsall in the league on Saturday.
The 44-year-old said: "We never have the feeling of giving up; it is in our DNA to be strong.
"My dream on taking the job was to the fill the stands, and now Saturday is very important to follow this up in terms of performance."
Crawley were successful with all five of their penalties, Vokes having missed Stoke's second kick, and Cioffi said they had been practising.
He added: "I trust the boys. I know we have good penalty takers. I have trusted them since day one of the season.
"We have started on a path and that is to work – we are on the right track.
"We are a side that will score goals and we have the right attitude and mentality. This was a great victory for the club and myself."