One match down for each Rugby World Cup heavyweight and Ireland have quickly reminded everyone why they were the dominant rugby nation on the planet last year, and why warm-up form counts for little.
Of all the opening salvos, undoubtedly it's the All Blacks who fired the loudest shot with their gripping and gritty win over the Springboks to rightfully regain the No 1 ranking.
The captivating brand of rugby and global appeal the All Blacks demand is evident in viewership numbers from France where 3.7 million watched their win over the Boks, marginally less than the 4.3m who tuned in for the last-gasp French victory against the Pumas.
Barely one week into this tournament and it's too early for wide sweeping statements or bold predictions. But aside from the All Blacks, Ireland were the most impressive of the other contenders, with the Springboks a close third.
Ireland's ruthless victory over Scotland didn't feature brilliant attacking movements to match the All Blacks but, then, those weren't their great strengths in 2018 either.
At the risk of getting ahead of ourselves it's worth noting that every team should improve from here.
Japan exhibited the first signs of nerves in their skittish opening win over Russia but those same twitchy jitters were widely felt, including from the All Blacks who threw offloads as if attempting to clock a game of hot potato during the early stages against the Boks.
Win or lose, with these first matches in the book, all teams should now be more comfortable on the field, settled in their surroundings and that will make for better spectacles across the board.
Scotland are justifiably copping a pounding from their home fans and media following one of their worst World Cup performances in history. Losing flanker Hamish Watson and halfback Ali Price for the remainder of tournament compounds worries they could yet lose to Japan in a match likely to decide the All Blacks' quarter-final opponents.
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While Scotland were poor in the 27-3 defeat, much of their high error count and poor decision-making owes to Ireland's supreme defensive work.
The 57-15 thrashing Ireland received from England at Twickenham just prior to the World Cup sparked surprise throughout the rugby world but the men in green were far from full-strength that afternoon and, with a view to replicating short turnarounds between matches in Japan, Joe Schmidt trained his side to the point of playing under fatigue.
In isolation that performance suggests Ireland were well on the decline or, more to the point, their defensive systems had finally been cracked. Not so now, it seems.
Since masterminding the Lions defensive resilience in New Zealand, Andy Farrell has become Ireland's not-so-secret weapon. This is precisely where Schmidt's men rattled Scotland in Yokohama.
Scotland's pack were monstered by Tadhg Furlong, James Ryan, Iain Henderson, CJ Stander and company but just as crippling is the clinical line-speed Ireland used to leave Finn Russell in a claustrophobic state. This aspect alone stifled virtually any Scotland attack and forced Russell, a gifted talent, to regularly shovel hospital passes sideways and kick aimlessly.
Combine Ireland's not always legal breakdown work with Conor Murray's kicking game – admittedly in favourable conditions as heavy rain fell during the second half – and when Ireland are allowed to dictate terms such as this, they remain as difficult as ever to combat.
Before the tournament I believed the Boks would hold the edge in a quarter-final standoff but if these similar styles indeed clash on that stage, with their strength and depth Ireland should arrive there with confidence, especially with their large pack of passionate travelling fans.
Elsewhere England lumbered to an uninspiring and underwhelming victory over Tonga who laid something of a blueprint by denying powerhouse No 8 Billy Vunipola any form of go-forward.
Eddie Jones needs to ditch the George Ford-Owen Farrell axis in favour of a more traditional midfield where Manu Tuilagi partners Henry Slade or Jonathan Joseph, both of whom are classy centres wasted on the bench.
Wales started well in an attempt to put the Rob Howley betting saga to one side but they were caught off-guard by the physical Georgian response early in the second half and their fascinating meeting with the Wallabies this weekend promises to reveal much more about respective credentials.
Fiji's size and physicality shook up the Wallabies who were very fortunate not to lose Reece Hodge after his high shot left damaging openside Peceli Yato concussed.
For the Wallabies to challenge, Michael Cheika must consider dropping flaky fullback Kurtley Beale and reinstating Will Genia at nine.
Finally, it wouldn't be a World Cup without French drama.
Le Bleus scored two magnificent early tries by embracing traditional French flair and have Argentina on the rack at 20-3, only for Los Pumas to turn the tide and steal the lead.
Camille Lopez's dropped goal saved France at the death and the feisty match finished with tempers spilling over after the final whistle.
Despite their second half collapse this was promising signs for France, who will now hope to stun England in their headline group match.
One week in, though, and the All Blacks and Ireland have set the bar.
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