Senior minister Peter Dutton says Malcolm Turnbull offered him the role of deputy Liberal leader after the first bitter leadership spill last year.
Mr Dutton says he put his hand up for the leadership in August because he believed he could win the election, which was about nine months away.
After speculation he had lost the confidence of multiple cabinet ministers, Mr Turnbull called a leadership spill on the Tuesday morning, beating sole challenger Mr Dutton 48-35.
"He offered me the deputy leader position," Mr Dutton told Sky News in a new documentary screening on Tuesday night that delves into the bitter battle.
"I said to him, given what had just taken place, that wasn't credible. It wasn't his to gift either."
Mr Turnbull denies offering Mr Dutton the role, which was held by Julie Bishop.
A second leadership ballot occurred just days later after Mr Dutton was able to get a majority of Liberal MPs to sign a petition calling for a challenge.
Mr Turnbull didn't fight for his role but instead chose to quit parliament, leaving Mr Dutton, Ms Bishop and Scott Morrison to fight it out for the leadership.
The documentary reveals a dinner conversation between Queensland coalition MP Luke Howarth and former NSW coalition MP Craig Laundy may have been the catalyst for the leadership challenges.
Mr Howarth told his colleague at the start of the divisive week he planned to tell Mr Turnbull to resign as leader at the next election.
"I was going to be very clear and maybe suggest that him and Tony Abbott might want to retire at the next election and let new leadership come through," he told Sky News.
"I was thinking of the party and thinking that perhaps it's time for new leadership."
The "heated conversation" rang alarm bells for Mr Laundy, who immediately spoke to his ally, Mr Turnbull.
"I rang Malcolm and said, I explained the nature of the heated conversation, the disagreement, the anger and the passion that Luke had," Mr Laundy said.
"I had a genuine concern that he could stand up the next day and say or do something that would be bad news."
Mr Laundy let Mr Howarth know he didn't think Mr Dutton would be a positive change for the Liberals.
"As much as Duts is a mate of mine, can you imagine how electorally popular he would be in NSW, Victoria and South Australia?"
Despite coming out on top at the end of the bitter week, now Prime Minister Scott Morrison says he believed Mr Turnbull could have led the Liberals to victory at the election.
"That was certainly my view," he said.
Australian Associated Press