And while he was still wary of the other main rivals in Penrith, Wests Tigers and the Roosters, Nightingale said it was another Parramatta charge that they were most concerned about.

"The top four are all hard to beat, but other than that the big threat will be Parra," he said.

"Mainly because after some of their disappointing games, they start to find some form like (Monday) and you know they're still a threat.

"I watched that game and you could see they were starting to put it together."

St George Illawarra are outright competition leaders after Penrith's shock loss to the Warriors on Sunday.

The Eels are in 10th place on the ladder, two points outside the top eight and 10 points adrift of the Dragons.

Nightingale said he was unsure if the Bulldogs could produce a similar charge from the bottom half of the competition, claiming their victory over Melbourne was hard to read.

Having been stripped of their competition points for salary-cap breaches, the Storm also had four key players - Greg Inglis, Cooper Cronk, Billy Slater and Cameron Smith - backing up from their roles in Queensland's State of Origin series whitewash.

"I saw a bit of the Dogs' game, but it's hard to take things out of the games against Melbourne. Especially post Origin and backing up, it must be hard to get up for them," he said.

The Dragons tackle another top-eight contender in South Sydney on Friday night.

The Rabbitohs missed an opportunity to charge into the top four after losing 18-14 against the Roosters.

Coach Wayne Bennett again named star recruit Mark Gasnier on the bench, with NSW Origin representative Beau Scott to start in the centres.

Nightingale said there had been few changes in the defensive structure since Gasnier's arrival.

"Not as far as what I do," he said.

"It's a bit different in some of the things that happen around me because Beau is just so strong defensively.

"But Wayne has his own style in place with defence and we don't go away from that because of a change in personnel."