Coach Wayne Bennett apologised to Rabbitohs fans who attended Sunday's dismal 56-12 defeat to Penrith in Dubbo and conceded: "We've got some issues".
"I'm sorry for all the fans here because they deserved better than that," Bennett said following the rout at Apex Oval.
Star fullback Latrell Mitchell's return from a four-week suspension failed to ignite South Sydney, who conceded five tries in a bleak first half and hardly troubled the undefeated Panthers in attack.
The Rabbitohs remain in fourth position, but having also lost 50-0 to Melbourne two weeks ago - albeit when they were decimated by injury - Bennett admitted to serious concerns for his side.
"The bottom line is we've played the top two teams in the past three weeks and they've both beaten us by 50 points," he said.
"We've got some issues ... It's just the way we're playing as a team."
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Bennett opted not to give veteran playmaker Benji Marshall any game time off the bench because he "wasn't going to embarrass him".
"We weren't defending well and Benji isn't known as the best defender the game's ever seen," Bennett said.
"We just couldn't stop them."
Mitchell, who was leading the Dally M Medal count before being suspended after round six, was below his best but still managed to run for more than 100 metres and set up a try.
"It was difficult for him at fullback in a game like that," Bennett said.
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The coach added when asked if he was confident Mitchell would rediscover his purple patch: "I'm not even confident the rest of them can capture the form they used to be in either."
Bennett rated representative lock Cam Murray "a slight chance" of returning from an ankle injury against the Eels next week.
"He's probably doubtful," Bennett said. "We thought we were missing Latrell and a few others and they all turned up today, so I don't think Cam Murray would've made too much difference."
