Cronulla look set to play NRL finals this season but are yet to beat a current top eight side after Friday's 38-12 loss to Penrith.
Defensive problems pulled the Sharks apart, while sloppy finishes to sets put them under more pressure.
It's a worrying sign for the seventh-placed outfit who face Newcastle, Sydney Roosters and Canberra over the last five rounds before play-offs.
While close losses to Parramatta and Melbourne were among the big games where they've fallen short this year they've hurt as much as any other.
Unconvincing in their two starts against the table-topping Pathers, the Sharks have now conceded 94 points to them in 2020 including Friday night's loss.
Losing Shaun Johnson in the lead up didn't help.
The Kiwi Test star did not train all week with a groin injury and also became a father when his wife Kayla gave birth to baby Millah on Thursday.
"I must admit, losing Shaun Johnson hurts us, we still haven't got Chad Townsend out there, so that's our starting halves, so there's two big casualties out there for us," said coach John Morris.
"But there's no excuse for our defensive effort, it was just horrible at times and not good enough for where we need to be.
"We've got to fix that really quickly.
"Every sort of half break we had didn't amount to anything and then the Panthers punished us pretty quickly after that. It wasn't our night.
"We'll go away with our tail between our legs but we've got to bounce back really quickly against the Cowboys next week.
"We need to see a good response, that's for sure."
While a bounce-back win would be good for morale, the Sharks need a big scalp to prove they won't be in the finals to make up numbers.
Johnson is expected to return next week as well as prop Andrew Fifita, although Chad Townsend remains sidelined with a calf injury.
"We need to start upping the ante and hopefully with Johnson back, Fifita available and Townsend available soon we can run out our best 17," Morris said.
"I'm confident if we do we can knock (top-eight) sides off."