Japan do have form, remember, for upsetting the established order. South Africa certainly remember.
The Brave Blossoms win over the Boks at last year's World Cup stands as the greatest of all cup upsets. So have Japan now added another sentence to the notion that they are rugby's most notable rising talent?
Mark Todd's despair was laid bare in technicolour at the equestrian park.
New Zealand sat nestled in the gold medal spot in the teams eventing today when the double Olympic champion, five-time medallist Todd entered the arena on Leonidas II.
His horse had dropped only a single rail in two years competition. He could afford to knock one down and New Zealand would still win gold. You would kind of fancy your chances.
This was to be the crowning achievement in the 60-year-old's glittering career, which has had him named Eventing Rider of the 20th century by the international federation.
Instead it went badly wrong.
The combination sent four rails toppling, New Zealand slid to fourth, out of the medals and Todd was left to ponder "one of the biggest lows in my career".
Talk to any horseman and they'll tell you: that's horses. Fragile beasts with skittery tendencies. Moments like that show up the skill of the finest riders. It just wasn't Todd's day.
His place is secure in the equestrian pantheon. The shame of it was that having battled back into second place going into the showjumping, after a modest dressage performance, it all went wrong, and of all the riders it could be in the saddle at the time, it was the greatest. That's the game.
Now think of the rowers, of whom a medal splurge has been expected. Two of the crews who were anticipated to, at the least, make their finals, the double sculling combinations of Zoe Stevenson and Eve Macfarlane, and Robbie Manson and Chris Harris, are gone.
No excuses, after all Mahe Drysdale, Emma Twigg, the lightweight men's four and of course Eric Murray and Hamish Bond had no alarms. Business as usual. Finals and semifinals beckon.
Rare indeed is the occasion when a Dick Tonks-coached crew falls so early in a major regatta, as did former world champions Stevenson and Macfarlane.
Out of 11 crews in Rio, three have now been eliminated. The odds are still good that New Zealand will bag a bumper crop of medals on the Rodrigo de Freitas course.
The men's Black Sticks stand on the precipice, after conceding the winner to lower-ranked Spain - 11th compared to New Zealand's eighth - in the last 30 seconds.
They have now lost two of their first three games and drawn one. Wins over lowly Brazil and the tough Belgians are musts if the Black Sticks are to avoid the heartache of an early exit from the Games.
New Zealand's swimmers have had a 'mare so far in the pool. Only backstroker Corey Main has made it as far as a semifinal. Three more missed out today. No real surprises there, but add it into the day.
Some brighter news. Sam Meech had fifth and sixth placings in the Laser to nudge up to third overall. But it's early days.
And the sevens men did beat Kenya in their second game of the day.
But the overall mood was grim. Call it a leveller of sorts. Or just call it sport.
