The error count was huge in a stop-start game where a powerful performance from Rabbitohs hooker Issac Luke helped Souths edge out a very young Penrith side 11-4.
The Panthers got off to the perfect start through a try to new recruit Tupou Sopoaga but things went downhill from there.
First a fumble at their own goal line allowed Jason Clark to score in the bonus zone, then a strong charge and offload from Issac Luke at the line allowed Chris McQueen to cross.
Despite some near-misses there were no points in the second half as both sides struggled badly to hold onto the ball, with Souths holding onto their 11-4 halftime lead.
Returning Rabbitoh Matt King said it was a thrill to be part of the Nines.
"I'm glad I came back, it's awesome fun mate, just like a big game of touch where you get to tackle each other," King said.
"I have some of my best mates in this team so it's awesome to put the boots back on with them.
"The body is not too bad, if you talk to me tomorrow afternoon it might be a different story."
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