The Cronulla Sharks scored three tries in a devastating seven-minute spell to overcome a half-time deficit and defeat the Brisbane Broncos 22-12.
Cronulla halfback Braydon Trindall produced one of his finest performances, scoring a try and setting up two others at Lang Park as the visitors rebounded after trailing 12-4 at the break.
The win ended a two-match losing streak for the Sharks and returned them to the top of the ladder.
Meanwhile, it was a second consecutive loss for the Broncos, who also gave up a half-time lead to the Gold Coast Titans at home two weeks earlier.
Brisbane coach Kevin Walters lamented the errors from his team, calling the second half the worst of the season.
"I'm not sure what happened, to be honest … probably our worst half of football," Walters said.
"Our first set in the second half was poor, with the ball, and it just got worse from there."
Cronulla's back five are a key strength and it was winger Sione Katoa who stepped his way through from a scrum with power and deception to narrow the margin to two points straight after the break.
Five minutes later, Trindall threw a dummy and blitzed his way past back-rower Brendan Piakura and the Sharks had the lead.
The Broncos had barely drawn breath after that double blow when a Trindall bomb was dropped by fullback Tristan Sailor and Blayke Brailey scored.
Sharks prop Royce Hunt came off the bench and was enormous with his energy and brute strength, while centre Jesse Ramien put in a stellar display to stake his claim to replace the suspended Joseph-Aukuso Sua'ali'i in the NSW State of Origin side.
Brisbane captain Patrick Carrigan, backing up from Origin with Queensland, backed up a burst by hooker Billy Walters to score the opening try under the sticks after 11 minutes.
But the Sharks returned serve when back-rower Siosifa Talakai started and finished a left-edge attacking movement with brute strength.
The Broncos defended set after set on their own line as the Sharks launched repeated waves of attack but came up empty.
As so often happens, the Broncos then took their first opportunity up the other end.
Hooker Tyson Smoothy scored when half Jock Madden's grubber kick ricocheted back into Madden's arms.
The Broncos, with several players backing up from Origin, ran out of gas in the second half and made multiple errors, with their last-play options poor.
Earlier, South Sydney earned back-to-back wins with a 46-12 victory over the Titans, while the New Zealand Warriors defeated the North Queensland Cowboys 42-12 in Townsville.
Re-live all the action in our live blog below.
That is all for the blog
We will wrap up the ABC Sport live blog there.
Big wins for Souths and the Warriors was followed by an impressive triumph by the Cronulla Sharks.
We will be back tomorrow as round 14 of the NRL continues.
Goodnight.
Brisbane coach Kevin Walters calls the second half the worst of the season
Brisbane coach Kevin Walters is fronting the media.
A clearly disappointed coach says errors cost his side in the second half.
"I'm not sure what happened, to be honest … probably our worst half of football," he says.
"Our first set in the second half was poor, with the ball, and it just got worse from there."
Broncos CEO doesn't think the four match Sua’ali’i suspension is enough
Broncos CEO Dave Donaghy has spoken to ABC Sport following Reece Walsh's injury in State of Origin.
He doesn't think the four match Sua’ali’i suspension is enough.
What are your thoughts?
Captain McInnes happy his team showed commitment
Victorious Cronulla Sharks captain Cam McInnes has spoken to ABC Sport after defeating Brisbane 22-12 at Lang Park.
The Sharks were coming off consecutive losses where they had gave up a total of 76 points.
But tonight, the Sharks were back at their destructive best.
They dominated the Broncos in contact, which brought delight to McInnes.
"Footy is a simple game, but if you want to play it the right way, it's a hard game," he tells ABC Sport.
Brisbane let themselves down with a slow start to the second half
Brisbane halfback Jock Madden has joined ABC Sport following his side's 22-12 defeat to Cronulla.
Brisbane had a 12-4 lead at half-time, but conceded three tries in the opening 10 minutes of the second half.
"We talked about [how] we wanted to come out firing in the second half. We did the opposite," Madden says.
"It wasn't good enough at the start of the second half and we couldn't come back from that."
FULL-TIME: Cronulla Sharks 22 def Brisbane Broncos 12
What an outstanding second half from the Cronulla Sharks.
A 10-minute blitz where they scored three tries — followed by punishing defence — has given the Shire boys a confidence-boosting win.
74' Trindall and Kennedy deny Brisbane
The Broncos came so close to getting back into this game.
A drop ball was collected by Deine Mariner who looks to run 85 metres.
Mariner is fast, but the last line of defence knocks him into touch.
It was a Braydon Trindall who made an ankle tap, then Will Kennedy completed the tackle into touch.
70' Katoni Staggs limps off the field
More issues for the Broncos.
Centre Katoni Staggs has just limped off the field.
His right knee is his problem.
He has gone up the tunnel.
65' Missed penalty goal: Sharks miss chance to extend lead to 12 points
The Sharks have missed a penalty goal after Brisbane were pinned for being offside.
The Sharks were attacking Brisbane's line again after another knock-on.
This time it was Deine Mariner who spilled a bouncing ball, while under no pressure.
Cronulla will get another chance as Brisbane will have a 20 metre drop out.
But Cronulla drop the ball near the Brisbane line.
The Broncos survive with the deficit still 10 points.
61' Jordan Riki passes HIA and returns
Jordan Riki, with a cut under his eye, has passed his HIA and is back for the Broncos.
50' TRY: Another Broncos error, another Sharks try
Brisbane has imploded to start the second half.
The Sharks, on the set after scoring, marched up field and put up a kick to Tristan Sailor.
Sailor drops it cold.
It lands in the lap of Siosifa Talakai and gives it to Blayke Brailey who scores.
48 TRY: Trindall scores and Cronulla take the lead
Brisbane have made two errors in their own end, and have conceded two tries from it.
This time it was Katoni Staggs who dropped the ball.
Cronulla are attacking Brisbane's line and halfback Braydon Trindall steps off his right foot, beats Brendan Piakura, and scores.
46' Jordan Riki off after an accidental boot to the face
Brisbane forward Jordan Riki has gone up the tunnel with a towel over his right eye.
Riki, while making a tackle, copped a stray boot which appears to have cut him.
43' TRY: Sione Katoa scores for the Sharks
Sione Katoa has scored early in the second half.
Off a scrum 10 metres from the Broncos' line — following a Tristan Sailor knock-on — Katoa beats Selwyn Cobbo and crashes over the line.
That is Katoa's ninth try of the season.
The second half begins at Lang Park
Cronulla kick-off with a big 40 minutes coming up.
The Sharks this time will run to the left of your screen.
Brisbane and Cronulla on a knife's edge
Tight first half, but I think the score reflects the state of play...
- Mike
Thanks for joining me on the live blog Mike.
This is shaping up to be a cracking game.
HT: Brisbane Broncos 12 leading Cronulla Sharks 4
Half-time at Lang Park and we have a cracker.
The Broncos' defence has been tested but the home side have held firm.
Brisbane's eight-point lead has been built on goal line defence and taking their opportunities.
The Sharks will believe they can score points tonight, while Brisbane will be buoyed with confidence.
33' TRY: Brisbane punish the Sharks with a try
Tyson Smoothy is over for the Broncos — against the run of play.
Cronulla had the ball for 26 of 27 plays, and it was all on the Brisbane line.
But the Broncos survived, got a relieving penalty, and then scored as soon as they tested the Sharks' line.
It was a grubber kick on the last play which hit a Shark, and the ball pops up perfectly for Jock Madden, who gives it to Smoothy for the try.
32' Brisbane's goal line defence survives again
Great work from Brisbane to repel the Sharks.
The away side threw everything at the Broncos.
Brisbane gets the ball, and a penalty.
Pressure relieved for now.
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