After last week's disappointing performance against Japan, Andy Farrell told his Irish squad to step up their game.
The team responded immediately.
The Irish side had struggled in the final stages against the All Blacks and required most of the match to find their rhythm versus Japan.
However, against Australia, they began powerfully, with the talented back shining brightest during a 46-19 triumph that represented the team's best display this year.
In his first test match appearance at the number 15 position, the player registered a three tries, competed brilliantly for aerial challenges and played exceptionally against the nation of his origin.
"Look, I've had a fairly challenging period with fitness issues really," Hansen commented.
"I missed being in this squad, I understand there's considerable talk about me not exactly being born here and I wasn't raised here, but I adore this team and this feels like home.
"Whenever I get to play for Ireland it's a honor, if you fail to deliver a performance you may not receive that privilege again.
"My whole approach this period was to take the field and do what I could do."
Manager declared: 'Excellent athletes require no justifications'
After 28 appearances on the wing, Hansen was given the number 15 role for the initial time with several players unavailable.
In his case, it was simply a matter of picking up where he finished during the warmer months.
The 28-year-old had been in superb condition before physical issues ended his aspiration of making the international team.
After come back last month, he suffered a foot problem that ruled him out for previous fixtures.
Farrell had indicated that the player was particularly motivated and these turned out to be not empty statements as the ex- club player gave his coach a positive selection dilemma for upcoming games.
"So my first reaction were, 'You better perform excellently in those two coloured boots!'," said Farrell, alluding to Hansen's decision to wear mismatched footwear.
"In fact I believed that was appropriate but it seems Mack just did that himself regardless. So he's drawn notice to himself before he's even begun.
"I said to him before the match, 'Excellent players require no justifications, they can get on with it and just play naturally, you can win the man of the match if you want,' and he went, 'Yeah, I agree.'
"So he's that kind of player, he trains thoroughly, he's has a great approach to understand his preparation and so that's why he slotted straight back in and he was able to perform naturally due to that."
The player's performance also earned praise from the rival manager, who stated he was the "exceptional opposition player" on the evening.
"In my view he was super, his experience showed to the fore," said the former international coach.
"Regrettably, Mack was probably the standout Australian performer on the pitch. He's has a great ability and he's such a strong contender."
When asked about what makes Hansen a good fit at full-back, the coach added: "Showing up in the middle of the pitch is a trait that he does from the wing regardless, but I suppose he's better in position for that more often.
"The player's aerial play was excellent, don't you think? I believed we didn't get bored of executing the correct thing and that was putting the ball again on them to secure field position.
"Why that was the correct thing to do is since it's the likes of Mackie who was getting the possessions returned, and other teammates, so [it's] quite pleasing."
Outside the star performer, there were multiple encouraging aspects for the coach.
Another player was excellent on his return to the number 10 jersey, the set piece and throw-in operated smoothly and another player did not look uncomfortable in his first start in the forwards.
But possibly most pleasing for Farrell was the team framing the match with two impressive periods.
The player's first two tries came in the first 11 moments while additional teammates registered in the closing exchanges after the other team had crossed, ensuring the Irish side concluded on a high.
"I thought we really let ourselves go and attacked the match right from the word go," stated Farrell.
"The way we handled various aspects during the match, especially them responding just before half-time and reorganizing ourselves and producing a performance like we did in the later stages, I believed as far as field position and being familiar with most of our game in that second half was really satisfying."
The strength of South Africa are next up for the team, in what could be viewed as an informal decider to last year's drawn multiple match contest on opposition territory.
The coach's team will need to reach a higher level to beat the consecutive title holders, but Saturday's defeat of the Australian team was a significant advancement in the correct direction after an uninspiring beginning to their autumn schedule.
