Still far from their best on Saturday night, the Sharks completed at only 59 per cent in the first half before showing signs of improvement to come from 6-4 down and win.
The victory at PointsBet Stadium kept the home side in fourth spot on the ladder and marked only their third victory in nine matches after exploding out of the blocks with a 9-1 start to the year.
It also killed off any slim hopes the Rabbitohs had of reaching the finals, on a night where they were forced to play without any of their first-choice backline.
Even still, Cronulla's victory was soured late with Trindall leaving the field and heading straight up the tunnel after experiencing hamstring tightness.
Braydon Trindall (L) chats with injured Rabbitoh Cody Walker (C) after the Sharks' win. (Mark Evans/AAP PHOTOS)
The Sharks are already without Nicho Hynes until the eve of the finals after a serious ankle injury, and now face the prospect of another potential change in the halves.
If Trindall was to be sidelined, one option would be to shift Blayke Brailey from hooker to fill the void.
Jayden Berrell, Mawene Hiroti and former Penrith talent Niwhai Puru are other options against Gold Coast next week.
"He (Trindall) has an awareness there, which made him flag it," Cronulla coach Craig Fitzgibbon said.
"He was tested, and it feels like there might be something there. But nothing went pop and there (was nothing to show) it's going to be an extended period if any."
Ugly as it was, Saturday's win was desperately needed for the Sharks.
Before this weekend, Cronulla's record since Magic Round had replicated the Rabbitohs' from the same period last year during their record-breaking collapse.
Talakai goes BANG 💥— NRL (@NRL) #NRLSharksSouths @telstra Moment of the Match pic.twitter.com/OFaBwW3JAHAugust 3, 2024
Damien Cook had moments of promise at dummy-half, while Jai Gray was particularly dangerous for the visitors.
Still deputising for Latrell Mitchell, the Souths No.1 opened the scoring when he made the most of a Sam Stonestreet error by cutting through the defence from a scrum.
Cronulla hit back through Sione Katoa when they created space on the right, but were denied twice in the first half through an obstruction and Stonestreet bobble.
And while they took the lead after the break through Stonestreet, the Sharks were asked to repel 19 straight tackles on their own line midway through the second half.
They survived, and when Siosifa Talakai ran over Michael Chee Kam in the lead up to a Trindall try, the game was broken open.
Kayal Iro then scored himself four minutes later when he chased down a Trindall grubberkick, putting the match beyond doubt.
"We've created a knack of putting ourselves in those situations, but I love what we did about it," Fitzgibbon said.
"We didn't panic or flinch.
"Based on tonight (we need to improve a bit). You can't give anyone that much opportunity.
"But if you need to hang in there and defend. That's good preparation."
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