Bulldogs coach Trent Barrett will seek further explanation for Lachlan Lewis's half-time sin-binning following the "uncharacteristic" brain explosion that cost his team the chance to cause a massive upset over the high-flying Rabbitohs.
Lewis was banished after a bizarre altercation with South Sydney's Cody Walker as teams walked from the ground at the break, crash tackling the Bunnies playmaker to the ground after the pair had been involved in a verbal exchange while leaving the field.
The incident sparked a melee between the teams, with Lewis marched for instigating the stoush, leaving his team to start the second half a man down in a hammer blow to his side's chance of causing an upset.
"I'd like to know what happened for Lachie to react like that," Barrett said.
"I didn't know you could get 10 minutes in the sin bin after play had been stopped and you're walking off at half-time - he didn't hit him or anything."
Down 10-0 after 20 minutes with the Rabbitohs looking as though they could score at will, the Bulldogs fought back to score two converted tries to take an unlikely 12-10 lead to the break.
Match Highlights: Rabbitohs v Bulldogs
But with Lewis off the ground, the Bunnies scored eight points through a converted try and penalty to regain the lead.
Off contract at season's end, Lewis is playing for his future at Belmore and his brain snap could prove costly but Barrett defended his player saying it was "completely out of character".
"Obviously something's happened for him to react like that - and it hurt us, they scored a try and kicked a penalty goal while he was off the field," Barrett said.
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"It was disappointing but that wasn't the reason we lost the game, we had our chances to win it, I thought.
"Every time we got down there we troubled them but the sad thing for us is, we only got down there four times."
Lewis atoned slightly when he returned to the field, juggling a pass and tapping the ball back to winger Jayden Okunbor for a try that kept the Dogs in the match.
But the Rabbitohs - who almost paid dearly for their first-half complacency - put the pedal to the metal in the final 20 minutes, scoring three tries to seal a win that cemented their place in the top four.
Jacob Host and Cameron Murray - one of three Rabbitohs players backing up from Wednesday night's Origin - scored tries to extend the lead but when Bailey Biondi-Odo, who set up the Bulldogs' opening try, kept things interesting when he pounced on a loose ball to score his first NRL try to reduce the margin to just four points.
Souths scored through their speedsters on several occasions but it was front-rower Mark Nicholls who sealed the deal when he loomed up in support to score just the fifth try of his career in his 100th game.
Walker places a kick for Host
Barrett praised his team's effort on the back of a strong showing against the Roosters last week and said there were good signs ahead with emerging players, strong signings and the addition of Phil Gould to the club.
"I think everyone can be extremely optimistic about where the club's heading, I do think we're heading in the right direction," he said.
"We obviously would have liked to win a few more games but with what's coming, the board's doing a terrific job and the appointment of Phil Gould yesterday gives us a little bit more stability and someone who knows what it takes to win and what a good football club looks like.
"We've got a great club here at Canterbury and we are heading in the right direction, so we know we've got some pretty high-profile players heading to the joint next year.
Lewis back onto the field to set up Okunbor
"But we've got an opportunity in the next seven weeks to finish the year really well too."
The Rabbitohs had a glut of possession in the opening stages but butchered two tries in the first eight minutes - once when Cameron Murray ran in front of Adam Reynolds as he was about to dart into the in-goal to score, while Taane Milne dropped the ball over the line under pressure from Lewis.
But it was not long before they were on the board.
Milne went over in the corner in the 13th minute to open the scoring and when Alex Johnston went over at the end of a backline catch-and-pass movement, the Rabbitohs were up 10-0 and looking as though they could score at will.
Whether it was complacency or poor management, a string of Rabbitohs errors turned momentum on its head and gave the Bulldogs the chance they needed to get back in the match.
The Bulldogs had just one set inside the Rabbitohs' 40m in the opening 10 minutes but it was shambolic, with the attack disorganised, players running backwards in an attempt to get out of each other's way and the movement ending when the ball was kicked out on the full.
But given the chance to reset, the Bulldogs bit back, scoring two converted tries before the break to take a 12-10 half-time lead.
The ball boys get around Milne after he gets the first try
The Rabbitohs finished with just one man on the bench after Campbell Graham and Liam Knight failed HIAs, while Johnston limped off with a hamstring injury early in the second half after scoring a try, while Latrell Mitchell did not back up from Origin on Wednesday night.
The Bulldogs will be sweating on the match review committee, with props Dylan Napa and Jack Hetherington on report for high tackles.
The win extended the Rabbitohs' winning run to seven matches and keeps them in third place on the ladder with a 14-3 record, while the Bulldogs (2-15) remain stuck in last place.
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