Not many AFL seasons have opened with two upsets of the scale we saw last weekend. One of them many of us are still scratching our heads about. But perhaps the other won't end up proving such an anomaly.
That the 2020 wooden-spooner Adelaide ended up on top of last year's runner-up Geelong was remarkable. It was the perfect start to a new campaign by the rebuilding Crows and a salient reminder to the Cats that you can't take any opponent for granted. But only a fool would now expect that result to be reflected across the next six months.
But the other big surprise? Well, without wanting to sound cocky, Sydney's stunning 31-point win over Brisbane, at the Gabba no less, I actually wasn't all that surprised about.
Most seasons have a "bolter" of sorts, a team emerging from nowhere to surprise the competition. I was confident enough John Longmire's Swans could be that team in 2021 to tip them to make the finals in eighth spot when I put together a predicted ladder a couple of weeks back.
Perhaps I'll be right, or perhaps Sydney will over have its moments in the sun but struggle to maintain its momentum, as happens to a lot of teams with a host of young and inexperienced players.
But there was something very encouraging about the way a team which ended up 16th on the ladder, with only five wins, finished off last season. What is arguably the first major rebuild the Swans have undertaken in the last two decades is taking shape beautifully, and with some speed.
There was something very encouraging about the way a team which ended up 16th on the ladder ... finished off last season. What is arguably the first major rebuild the Swans have undertaken in the last two decades is taking shape beautifully.
Last year was the first time Sydney had missed out on playing in finals in consecutive years since 1994-95.
On a very superficial level, with a host of experienced players having departed in recent times and a 34-year-old Lance Franklin failing to get on the park at all, anyone could be forgiven for seeing at least a few seasons of struggle ahead.
But there some genuine flickers in that late-season darkness in 2020. Two impressive victories over aspiring finalists in Greater Western Sydney and Melbourne. And the Swans pushing eventual runner-up Geelong to within a kick in the final game of the season. It wasn't on the back of the usual suspects or Sydney's famed contested, slogging brand of football, either.
The Swans began to add some more strings to their bow via the inclusion and development of a clutch of eager young faces like the exciting Justin McInerney, Hayden McLean, James Bell, Dylan Stephens and Sam Wicks.
Against 2020 preliminary finalist Brisbane last Saturday night, the development stepped up another notch with three teenagers - Errol Gulden, Logan McDonald and Braeden Campbell - making their AFL debuts.
And these were no ordinary debuts. Gulden kicked three goals, set up another three and had 19 disposals in a performance good enough to win him the season's first Rising Star nomination. Highly-rated key forward McDonald chipped in with three goals. And the classy-looking Campbell also played a key part.
All-up, the Swans had half-a-dozen players with 10 or less AFL games to their names. Symbolism doesn't come a lot more potent than the statement they made collectively.
But so did Sydney's best and fairest results last year. While the Bob Skilton Medal was won by Jake Lloyd from Tom Papley and Luke Parker, four of the last five spots in the top 10 were filled by up-and-comers like James Rowbottom, Jordan Dawson and Ollie Florent.
The other member of that quartet, Callum Mills, is now entering his sixth AFL season. What many forget, though, is his still relative youth at 23.
After some issues with injury and durability, the win over Brisbane saw Mills finally make his permanent and long-awaited move to a key midfield role with maximum impact, the former Rising Star winner finishing up best-on-ground with 29 disposals and a couple of goals.
Can the Swans sustain it? Well, while there are a number of youngsters for whom the stresses and strains of a long AFL season will inevitably take a toll, Sydney nonetheless also has plenty of experience.
Parker, Lloyd, Papley, Josh Kennedy and Dane Rampe are the most obvious leaders. Isaac Heeney, like Mills, is another young veteran whose performance last Saturday night was pivotal, and has the football world at his feet.
And the biggest statement of the lot? Perhaps it's the fact that Franklin's long-awaited return to senior action this week against Adelaide is, far from the difference between the Swans having a decent show or not, more like the definitive cream on the cake.
Franklin as an adornment? That's certainly a pretty decent dollop of cream to be able to add. But Longmire and his coaching crew look to have already baked a cake which, even without the decoration, is looking tastier by the week.