Star Cronulla signing Addin Fonua-Blake has admitted to checking-out during games, but says the Sharks must urgently hit form to resuscitate their NRL season.

Sixth-placed Cronulla have the worst win percentage against the other top-eight sides, claiming only one win from seven this season.

Since their shock five-point win over Melbourne in round 11, Craig Fitzgibbon's men have won just one game and fallen to three top-eight sides.

Fonua-Blake was touted as the missing piece in the Sharks' premiership puzzle on arrival from the Warriors this year, but admitted he has been below his best during the form slump.

"I've had a few mental lapses in the game on the weekend and in the few games I've dropped on along the way this year," he said.

"I want to be doing everything I can to make sure that I help the team perform as best they can."

Sunday's rematch against the Storm at AAMI Park is shaping to be one of the biggest tests to date for the Sharks, with just two competition points separating fifth from 11th.

"(I) feel like every game is pretty urgent. We don't want to be where we're sitting at the moment," Fonua-Blake said.

"We've dropped a few on the run now and we can't afford to drop any more."

Halfback Nicho Hynes has been highly criticised for his contribution to the team's performance, but Fonua-Blake dismissed the idea.

"It's not right that Nicho wears all the punishment and all the pressure is on his shoulders," he said.

"I'm pretty sure out of the 17 blokes that took the field 17 of us would put our hand up and say we weren't good enough. So Nicho's unrightfully been the easy scapegoat over a few years."

Rachel Jackson - AAP