Powell was furious with his side’s display especially on the back of producing their best performance of the season with a 38-10 success over champions Leeds Rhinos at Magic Weekend.
They were fragile from the start as Kyle Amor crashed through for the first of Saints’ eight tries as early as the third minute and, though Castleford rallied late on, they were 34-4 down after an hour.
It was a sobering sight for last season’s beaten Grand Finalists who, more than anything, prided themselves on their defence when racing to the League Leaders’ Shield by a record 10 points.
“That was hugely disappointing,” admitted Powell, whose side missed out on a return to the top-four.
“We were waiting to see if last week was an upturn or just a flash in the pan.
“We’re getting some tough things happening to us. We lost Benny Roberts again which meant a complete reshuffle with no Jake Webster or Joe Wardle (at centre) so that put us out of sync completely.
“But still. I watch (depleted) Hull at the moment and I think they have some balls about them.
“I don’t think we have any when we get put under pressure by the better teams.
“We just couldn’t defend tonight.”
It was a third defeat to Saints this year and the second time they had 40 points put past them by Justin Holbrook’s thrilling side.
Compared to their usual high standards, it was alarming.
But Powell insisted: “I don’t think we have high standards at the moment.
“If you watch how St Helens defended tonight I think that’s high standards.
“We played a lot of football towards the back end. At times in attack I thought we were really good but we haven’t got high standards in defence. Nowhere near. “And that’s what you get (defeat) if you haven’t got high standards.
“We’ve got too many players who don’t really care about defence. We cared about defence last year and I don’t think we do at the moment.
“The same players are saying the same things in the changing room but it has to be about more than that; it has to be about individual integrity towards your job.
“We need to work harder and we need to be tougher for 80 minutes. We gave Saints 40 minutes of a tough game a fortnight ago (in the Challenge Cup) and we did it for 20 minutes tonight.”
As well as losing Roberts to a hamstring strain on his first game back from a calf injury, Castleford also saw prop Junior Moors depart with a first-half concussion.
Powell, who side head to struggling Hull KR next Friday, saw winger Greg Minikin have two ‘tries’ disallowed as he fumbled over the line and then had a foot in touch.
“I thought we started with a real verve about us with the ball and put them under pressure but we just couldn’t defend,” he added, while also lamenting the standard of officiating.
“Players have got to be able to do their jobs better. If you can’t finish tries, if you can’t make tackles, if you can’t get decisions right… there was too much of that tonight.
“And Saints are a very good team. They’re playing with confidence. And they’re not getting what we’re getting at the moment which is having to reshuffle our team all over the place.
“But you still a expect a degree of toughness from your team and I thought that was missing for too much of that game.
“Too many of our players have to change - they have to change - if we are to have a chance of doing anything.”