Facing off directly against older siblings Michael and George, Robert crossed twice in the first half to edge the Rabbitohs to a two-point lead at the break on Thursday.

However the Eels' defence fell off dramatically and the Rabbitohs took full advantage, with Robert completing his dream night with two more tries on the way to their 11th win of the season.

They temporarily move to the top of the ladder ahead of Penrith and St George Illawarra, who are yet to play this round, on points differential, while the Eels remain rooted to the bottom of the table.

It was also their seventh straight win - the first time they've achieved the feat since 1994.

The hosts had hoped to build on their drought-breaking win over North Queensland last week and appeared on their way when a Bevan French try yielded an eight-point lead in the 25th minute.

But once the Rabbitohs found their feet, Parramatta were simply no match for the league's best attack in front of a disappointing crowd of 8047 at ANZ Stadium.

Tries to Robert Jennings and Alex Johnston in the space of three minutes gave the visitors the lead at the break, with Johnston completing a brace soon after the resumption.

Jennings claimed the second hat trick of his career after skipper Greg Inglis found himself in the backfield, and he then registered his fourth on the hour-mark.

He finished the night with a game-high 163 metres, six tackle busts and four line breaks, while Johnston also had a combined six line break and try assists.

Consolation tries to Eels pair Jarryd Hayne and Josh Hoffman saved some face for Brad Arthur's side, with Hayne now scoring three tries in his two matches since returning from a hip injury.

With State of Origin II on Sunday week, Inglis was given an early rest after 68 minutes, while their NSW contingent also finished unscathed.

Rabbitohs coach Anthony Seibold admitted he was initially worried about how Robert Jennings approached coming up against both brothers for the first time.

He's not done that before. He's played against Michael before. Spoke to him about being aggressive, getting some early carries and get himself into the game," he said.

"He did a really good job and the guys inside him - Greg and Cody (Walker) did a great job setting him up for a couple of those tries."

Eels coach Brad Arthur described some of his team's play as reserve grade standard.

"There was a lot of good effort and a lot of good performers for us but some big decision-making or errors on play one out of red-zone really cost us," he said.

"I don't want to be rude to Souths. They executed their play really well but we've seen them plays a thousand times, we defend them a thousand times at training. We just weren't aggressive."

Australian Associated Press