Herring will soothe the blow of Cronin's injury for Ireland
Gone are the days when Ireland reserved their worst performance for the last game of the season as the lure of the beach proved too strong. Joe Schmidt put paid to Irish eyes being taken off the ball.
This series in Australia is likely to go down to the wire this morning and Ireland have the momentum at Allianz Stadium after levelling matters with a commanding performance last time out.
A week on, they can make one final bit of history at the end of a remarkable campaign and they are favourites to do so, but the changes forced on the head coach must be a concern.
While the blow of losing hooker Sean Cronin on the eve of the match is eased by the form of Niall Scannell and Rob Herring, who have both performed well on tour, it is the absence of Dan Leavy and Garry Ringrose that threatens to undermine the Irish effort.
The inclusion of that pair helped turn things around in Melbourne.
Leavy may have lasted only 40 minutes, but his physical presence was crucial to the way Ireland dictated the pace and his relentless industry will be missed for this decider.
Ringrose adds subtlety to the Irish attacking game and good decision making in their defensive line.
Schmidt has still named a strong side for this clash, but both the midfield and back-rows look a tad unbalanced and this Australian side can exploit vulnerability ruthlessly.
Up against a back-row famed for its twin-openside approach, Schmidt has picked two No.8s and a blindside, while in the midfield Bundee Aki and Robbie Henshaw both do their best work at inside centre.
That's not to say the old Connacht pairing can't work well together and Henshaw will be keen to fix the things that went wrong in defence in the first Test, but they will also need more from him in attack if they are to create openings in the Australian rearguard.
That has been Ireland's issue on this tour. Despite owning possession and territory last weekend, they managed only two tries. In Brisbane, they never crossed the whitewash.
Operating on limited possession, the Wallabies have been far more clinical and look the greater threat when they have the ball.
In Melbourne, the tourists were able to deny them the openings, but Michael Cheika and his backroom team have spent the last week working on strategies to get their hands on the ball for longer.
Ireland did well to keep David Pocock and Israel Folau out of the second Test, but repeating the trick will prove difficult.
Cheika has been focusing on Ireland's latch-carry, where the ball carrier is supported by the weight of a second player to win the collision, while he has also been drawing attention to Ireland's 'escort' lines to put Folau off his stride as he chases kicks.
Referee Pascal Gauzere will be aware of their concerns, but Ireland insist they are doing nothing wrong.
The inclusion of tall blindside Lukhan Tui should strengthen the Wallaby lineout which has creaked thus far, while they will be determined to cut down their penalty count.
Ireland's mission is to put them under so much pressure that they are forced to infringe.
The pack might be missing a specialist No.7 but it is full of ball-carrying talent and set-piece excellence, Jack Conan's capacity to offload could free up some space in behind and the half-backs are the trump card. Conor Murray and Johnny Sexton have been outstanding all season and their capacity to calmly manage the game makes Ireland so hard to beat.
Australia have already managed it and have the ability to ramp up the pace of the game to a level that Ireland find uncomfortable.
Cheika is promising a physical approach.
"Everything depends on having the platform laid up front," he said.
"Nothing happens without that type of physicality and that type of accuracy around the attacking ruck to be able to launch any of these things."
Although Peter O'Mahony spoke of an Irish fear that a failure to perform could result in a big defeat, it seems unlikely that either of this vintage series will be won at a canter.
It may be the end of a long season, but the skipper is ready for one final push.
"There's 23 of us who have been picked to play for Ireland. That alone gives you all the energy in the world. I know you've got to go and bring it and that's a different story," he said.
"It is the last day of the season and guys have got different knocks and bruises but that's just put to bed when you warm up.
"It just leaves your body. The buzz during the week - there's nothing better, and that will drive you through any pain or tiredness that you might feel."
At 1-1, it is perfectly poised for a grand finale and victory would be a fitting end for a superb Irish season to conclude.
Australia have other ideas and their greater attacking threat could just edge a tight game at the death.