Warriors coach Stephen Kearney expressed his disappointment with his team's second-half collapse that saw the Panthers steal victory in Saturday's clash at Pepper Stadium.
The visitors were left stunned after letting a 22-point lead slip, conceding four tries in 12 minutes after a dominant opening half.
Basic errors from the Warriors and a swing in possession saw the momentum shift towards the Panthers after the break and Kearney's men struggled to keep up or show resilience in defence.
The result was the biggest comeback the Warriors have conceded in their 22-year history.
"The Panthers turned up the intensity in the second half and we just couldn't match it which was the disappointing part," Kearney said.
"We just couldn't go with them.
"We spoke about it at half-time, about making sure we maintained the pressure but we just didn't deliver on the action."
Penrith finished the contest with 56 percent of possession after the Warriors controlled the game well in the first 40 minutes.
The home side turned it on to deliver a second-half performance with an 87 percent completion rate and 16 offloads that constantly threatened the Warriors defence.
"When you give a side like the Panthers space to grow then you're asking for trouble and I don't think we responded very well… Very disappointing," Kearney said.
"When you get into a position like we did at half-time it's about making sure you go on with it and maintain the intensity by sticking to a process and I thought we went that far away from what we've been working on.
"That's the disappointing thing about it all."
The Warriors have a terrible record in Australia, winning only seven games in the last three years, but Kearney wasn't keen on putting the blame on travel.
"I don't think it comes down to our process in travel for away games, we mentally switched off or whatever the case was in the second half," he said.
"We've had three challenging games the last three times we've [travelled] across here with Canberra, Melbourne and now the Panthers, but I thought we didn't help ourselves today.
"It wasn't good enough."
Warriors skipper Roger Tuivasa-Sheck admitted it had been hard to remain positive while the Panthers were on a roll with the side forced to defend their line for most of the second half.
"It was frustrating because we're all out there saying the right things but we just couldn't deliver on the actions," Tuivasa-Sheck said.
"It was tough mentally to just try and get the boys back into it and forget about the quick tries but we didn't show any actions."
Meanwhile, Warriors centre Solomone Kata was the only casualty to come out of the game for the visitors after picking up a calf injury and Kearney said the 22-year-old would be monitored upon returning to New Zealand.
The Warriors face the St George Illawarra Dragons at Waikato Stadium in Round 12 on Friday.