Newcastle boss Dean Richards slammed his players' first-half performance in Sunday's loss to London Irish at the Madejski Stadium.
Richards described his side's effort in the opening 40 minutes as "one of the worst I have ever seen" after conceding six tries.
The Falcons trailed 40-12 at half-time before delivering a much better effort in a scoreless second-half.
The defeat means the Falcons are seven points ahead off bottom-placed Worcester, with both sides having three matches left to play.
"It was incredible, we lacked any composure or intensity," said Richards.
"Some of our boys thought we are already safe from relegation, we conceded the first three tries through our own mistakes and were always chasing the game.
"London Irish had nothing to lose, we knew they were going to throw the ball around from the off and we had to cope better than we did."
Richards made three substitutions during the interval, including the introduction of scrum-half Mike Blair and fly-half Joel Hodgson who gave the side more direction, but despite their improvement they could not add to their points tally.
"I made it perfectly clear what I thought at half-time as the boys knew they played badly," added Richards.
"In the second half there was a lot of endeavour but we still lacked structure and composure."
London Irish director of rugby Brian Smith was delighted with his team's performance.
"We definitely got a flyer, with charge-downs etc, but I'm pleased we went on with it," he said.
"I'm actually happier with our second half performance as we put in a massive defensive effort not to bleed a try or two which is difficult when you are that far in front."
The Exiles now face difficult away fixtures against Northampton and Gloucester which Smith admitted would be tough.
"We are safe but can't get in Europe so it's an unusual situation," he added.
"But the signs are good as we are working hard for each other.
"To lose James O'Connor with a hamstring problem 10 minutes from the end was a blow. We will have to assess him but Tom Homer is a ready-made replacement should we lose James."