The opening batsman delivered his second big century in the space of a week as he fired 148 from 116 balls in Australia's thrashing of Scotland in Edinburgh on Tuesday.
It followed the 26-year-old's record-breaking 156 from 63 balls in last week's Twenty20 match against England, the highest individual score in T20 international history.
QUICK SINGLE: Scotland v Australia ODI wrap
The innings against Scotland marked Finch's breakthrough in the 50-over format, having never scored higher than 38 in seven previous knocks.
Given a chance in the Australian summer, Finch failed to take it as he averaged just 15.00 in matches against Sri Lanka and West Indies.
The Victorian believes he wavered from his natural game and says the key to the form revival has been trusting his aggressive style of play, or as some have dubbed it, "Finch hitting".
"The last time I played for Australia I probably tried to bat a little more how I thought I should be batting rather than backing my game and backing what got me picked in the first place," Finch told AAP.
"I'm mindful this time to play my natural game and play with instinct and not be afraid of the outcomes.
"Now and then you tend to look too far ahead and worry about the outcomes rather than the process and I'm confident now the process I've got can work for a long period of time."
Finch was overlooked for June's Champions Trophy and spent more than a month with Australia A before earning a recall for the limited overs tour of the UK.
With David Warner omitted from the squad to face England, Finch will take over the mantle as chief aggressor in the top order and he's keen to cement a long-term spot in the side.
"I hope so. But a five-game series is a long series against England," Finch said.
"Hopefully I can get another couple of big scores and we'll see how we go.
"I feel really good at the moment. I feel like I'm striking the ball well, like I'm mentally pretty clear and that's a real bonus for me."
Australian captain Michael Clarke said Finch was reaping the rewards for learning to play his way.
"It's a really positive sign, not only for Aaron but for the team. Hopefully this is just the start," Clarke said.