Penrith coach Ivan Cleary was far from satisfied with the side's 80-minute performance during their 28-16 win over the Sea Eagles but gave credit to Manly for pushing them to their limits.
The Panthers held their nerve against a gallant Manly outfit to secure their eighth straight win to start the season - the best by an NRL club since Melbourne in 2012.
A long-range try with five minutes left from Sea Eagles winger Jason Saab set up a grandstand finish in Bathurst after the Panthers enjoyed a 22-12 lead midway through the second half.
However, a miraculous late try to Stephen Crichton via Panthers back-rower Liam Martin in response killed off any chance the Sea Eagles had of snatching victory in front of a crowd of just over 5,000 at Carrington Park.
"I was happy with our try-line defence in the second half [but] I wasn't happy with how we came out of the sheds," Cleary said.
"I thought we lacked energy and intent. Manly were the opposite and rightly so got on top for a period.
"But I thought we scrambled away and made some big stops in that period.
"The first half I was reasonably happy with but I thought we gave them a try … the [Tom Trbojevic] intercept try was a big turning point."
In a battle between State of Origin halves Nathan Cleary and Daly Cherry-Evans, it was NSW halfback Cleary who set up two tries to steer the Panthers to a comfortable lead early.
Match: Panthers v Sea Eagles
Round 8 -
Venue: Carrington Park, Bathurst
After the Panthers pummelled the Sea Eagles 46-6 a month ago, Des Hasler's side showed vast improvement against the title heavyweights but not enough to extend their own three-game winning streak.
An early penalty goal via Reuben Garrick gave the visitors a 2-0 lead early but that quickly evaporated when the Panthers went 90 metres through Brian To'o and Matt Burton.
To'o's ducking and weaving efforts were combined with a charging run over Cherry-Evans before Burton's boot sent Dylan Edwards over the line in the same play.
The Panthers were in again two minutes later with that man To'o finishing off a Jarome Luai cut-out ball after the home side were carried down the field by back-to-back six-again calls.
Only a poor offload by James Fisher-Harris, which was intercepted by Tom Trbojevic, who raced 65 metres to score against the run of play, could stop the Panthers in the first half.
Miraculous Martin taps it back for Crichton
A clever kick from Cherry-Evans ricocheted off the posts to land back in the hands of the Sea Eagles playmaker, who helped narrow the lead to four.
The Sea Eagles dominated with four repeat sets on the Panthers line to follow but couldn't come up with points in a frustrating period for the visitors.
The Panthers got back into their groove after repelling a barrage in attack, before Crichton's put-down sealed the result.
In concerns for the Panthers, back-rower Kurt Capewell didn't complete the game due to a rib injury, while centre Matt Burton was placed on report late for high contact on Manly's Martin Taupau.
The tackle occurred from the kick restart directly after Saab narrowed Penrith's lead with four minutes left.
"It was a scare when young Saab scored," Cleary said.
"But was good to get the job done at the end of the game."
The Panthers return to Penrith on Friday to host the Cronulla Sharks at BlueBet Stadium in round nine.