Ben Carroll is beginning his first full day as Victorian premier, just four months out from the state election.
Mr Carroll emerged from a chaotic caucus meeting yesterday as the third Labor leader this term.
The 51-year-old has already promised significant reform, but questions remain as to how this will be achieved with so little time until the state poll in November.
After the vote yesterday, Mr Carroll staked his leadership on launching a royal commission into alleged corruption on the taxpayer-funded Big Build.
"Let me make one thing very clear: I am not Daniel Andrews. I am not Jacinta Allan," Mr Carroll declared at a press conference shortly after he was sworn in at Government House.
While he is yet to detail the terms of reference for the royal commission, Mr Carroll said it would be expansive and established as soon as possible.
Ben Carroll and Gabrielle Williams address the media at their first press conference as Premier and Deputy Premier. (ABC News: Danielle Bonica)
Reform to the state's anti-corruption watchdog IBAC will be introduced this term, Mr Carroll said.
The new premier also pledged yet-to-be-detailed law-and-order changes, as well as a shift in focus towards businesses.
"I will do things differently, because different times require a new approach,"
Mr Carroll said.
"In my government, integrity will not be optional."
In the meantime, Mr Carroll will need to rejig his frontbench.
His own education portfolio will be up for grabs, and he will need to pick a replacement for his predecessor Jacinta Allan.
Several sources told the ABC that Mordialloc MP Tim Richardson would enter cabinet, but other changes to the previous Allan ministry are yet to be revealed.
Yelling from the partyroom a soundtrack to chaotic caucus meeting
Yesterday's leadership battle unfolded behind closed doors after a rollercoaster period for Labor, that began with Ms Allan vowing to contest a party ballot on Monday, and ended with Mr Carroll elected unopposed by lunchtime on Tuesday.
Ms Allan had on Monday vowed to fight on.
But on the same day, Mr Carroll, then her deputy, stated his intention to challenge for the leadership.
By Tuesday morning, Ms Allan realised she had lost the support of her caucus.
She resigned as premier at 9:30am, despite claiming she would win a ballot of the entire Victorian Labor membership.
As she announced her departure from the state's top job, Ms Allan — who was the youngest ever woman MP elected in Victoria and just the second woman premier — put her support behind whoever was victorious in her place.
It seemed like the stage was set for Mr Carroll's ascent.
But once the 10am caucus meeting was underway, Ms Allan's key ally, Attorney-General and Planning Minister Sonya Kilkenny, made her own play for the leadership.
Outgoing premier Jacinta Allan walks into Labor caucus meeting flanked by a loyal Sonya Kilkenny, who would make a brief bid for leadership. (ABC News: Danielle Bonica)
The caucus meeting spanned almost two hours, and yelling could be heard from the halls of parliament.
At one point, Ms Allan could be heard saying loudly, "Hang on, hang on, one at a time."
When Ms Kilkenny withdrew her candidacy, it was in exchange for securing an agreement — this included that she would keep her own roles in cabinet, that Mr Richardson would enter cabinet, that there would be no bloodletting, and that all MPs would sign Mr Carroll's nomination form.
Ultimately, Mr Carroll walked out as the Labor leader alongside his new deputy Gabrielle Williams.
Ms Allan is yet to declare whether she will remain in parliament, though she's expected to retire ahead of the state election in November.
The former premier said she would address her supporters in Bendigo, where she has held the seat of Bendigo East since the 1999 state election.
Shorten backs switch to Carroll
On Tuesday night, former federal Labor leader Bill Shorten said the ALP's Victorian wing would have faced "extinction level results" if Ms Allan had remained premier.
"I think, as much as people don't want to hear this in Labor, I think they were facing extinction-level results worse than 1992 when Jeff Kennett wiped out Labor," Mr Shorten told 7.30.
"I understand why people acted."
Former federal opposition leader Bill Shorten told 7.30 that the switch from Jacinta Allan to Ben Carroll made political sense for Victorian Labor. (ABC News: Mark Moore)
As to whether Mr Carroll could do enough to keep Labor in power, Mr Shorten said he felt he would make them competitive at the November state election.
"I think he can move them from the low 20s to at least the mid-30s [per cent of the vote]," he said.
"[Mr Carroll is] doing this to make sure the can try to win and make Labor competitive. I think he will give them a bump.
"Changes sometimes work, sometimes they don't. But I can think of plenty of examples where they have worked."
Opposition Leader Jess Wilson will now face Premier Ben Carroll in the 2026 Victorian election campaign, with the state heading to the polls in November. (ABC News)
Opposition Leader Jess Wilson faced Mr Carroll in question time on Tuesday, aiming at the new premier whose leadership bid came after recent declarations of support for Ms Allan.
"Only last month, [Ben Carroll] said: 'I've got a young daughter at home, and I couldn't be more proud to make sure she grows up knowing I supported Jacinta Allan.'" Ms Wilson said.
"How can Victorians possibly believe this premier can act with integrity when governing Victoria, when he can't even be honest with his own daughter?"
Victoria's election will be held on November 28.
