Ill discipline on both sides of the ball proved to be the undoing of the Rabbitohs on Friday night, with their winning run of six matches halted at the hand of the Eels.
Alex Johnston - of Saibai Island descent - bagged a brace, with Campbell Graham scoring the Rabbitohs' third try of the night, while proud Bundjalung and Yuin man Cody Walker dazzled with three try assists.
It was an undesirable start for the Rabbitohs as Parramatta winger Sean Russell scored the first try of the match after just three minutes, but the hosts were just as quick to reply as Alex Johnston touched down following a brilliant one-on-one strip from Latrell Mitchell.
The Rabbitohs' champion fullback then halted a barnstorming Maika Sivo, before Isaiah Tass brought down opposite Will Penisini as the defence held on after absorbing multiple sets on their line.
The defensive fortitude stood tall as Johnston saved a further four points by bundling Russell over the touchline, as both sides looked to add conviction to their hits.
Ill discipline from South Sydney handed Parramatta cheap territory, with second-phase play proving an issue, and a break from halfway resulted in Bailey Simonsson touching down in the opposite corner to extend their lead to eight.
Needing to reel back momentum, the Red and Green looked to go out wide, and it was the Walker-Mitchell combination lighting up Allianz Stadium to send Johnston over for his second - with Mitchell's conversion bringing the scoreline to 12-10 at the break.
Both sides returned to the field with plenty of intensity, with the Rabbitohs gaining possession and momentum through Parramatta errors - and Walker's sleight of hand saw Campbell Graham in for his twelfth try in as many matches.
But just as they had gained the lead, a kick out on the full handed their opponents possession and an opportunity for Bryce Cartwright to touch down, with the difference back to two points following Mitchell Moses' conversion.
Yet another kick on the full cruelled the Rabbitohs, and moments later a wayward kick bounced perfectly for the Eels as Simonsson crossed for his second, with the deficit back to eight points as the match entered its final quarter.
Poor discipline continued to hand the Eels momentum through the middle of the field, and while Graham and Mitchell came to the rescue to bundle Sivo into touch, Parramatta replied in kind to do the same to Taane Milne.
Multiple penalties saw Dylan Brown in the clear and the Rabbitohs defending their line once more, with a deft kick finding the five-eighth just millimetres from the line, giving the Eels a 14-point lead to seal the result.
The Eels then crossed once more in a cruel end to the match through Will Penisini, with the final scoreline 36-16 in favour of the visitors.
The Rabbitohs made ten errors and gave away six penalties in the 20-point loss.
Parramatta shocked the crowd by scoring the first try of the match and taking a 6-nil lead after four minutes through Sean Russell.
After being denied moments earlier, Alex Johnston found himself over the line after a brilliant one-on-one strip from Latrell Mitchell, which was enough for Cody Walker to send the winger over the line.
The Eels were next to strike back through Bailey Simonsson with just over ten minutes remaining in the first half, extending their lead to 12-4.
With time ticking down, Walker and Mitchell combined to send Johnston in for his second and close the deficit to two points going into the break.
A slew of Parramatta errors allowed the Rabbitohs to camp in the red zone, and Cody Walker's sleight of hand allowed Campbell Graham to burst through and give the Rabbitohs the lead.
Parramatta were the next to score through Bryce Cartwright after a kick out on the full handed over cheap territory, with the difference back to two following Mitchell Moses' conversion.
The Eels backed up their effort as Simonsson bagged his second through a wayward kick, as the Rabbitohs needed to claw their way back from an eight-point deficit once more with 20 minutes remaining.
Parramatta sealed the result with nine minutes on the clock, with Dylan Brown touching down just millimetres from the line, before Will Penisini added another try in the dying stages.
Play of the Game
Needing to swing back momentum with minutes remaining on the clock before half-time, the Rabbitohs' Indigenous stars combined to close the deficit at the break.
Down 12-4 with less than five minutes remaining, the Rabbitohs went wide through Cody Walker, who found Latrell Mitchell on his inside, before bamboozling the defence and regaining possession.
The veteran five-eighth looped a pass to flying winger Alex Johnston, who crossed for his second of the night and bringing the Red and Green crowd to their feet.
Putting the cherry on top, Mitchell's sideline conversion brought the deficit to just two points as the sides headed into the sheds.
The Rabbitohs return to Accor Stadium to face the Canberra Raiders next Saturday night, with a number of up-and-comers set to don the Red and Green with a host of State of Origin representatives in camp.