KEY POINTS:
The Blues went swimming with Sharks last night, got caught in the jaws and were spat out bruised and mangled.
Those who reckon a Blues versus Crusaders final is a fait accompli will have had their conviction shaken both by the frailty of the home side and the outstanding performance by the Sharks.
Defeat on home soil so close to the playoffs should serve as a wake-up call every bit as loud as the fire alarm that went off minutes before kickoff and delayed proceedings for 15 minutes.
From cruising along just dandily, thanks very much, the Blues are potentially now vulnerable.
They head to South Africa today for a three-match tour that will pit them against the Stormers, Bulls and then the Force on the way home.
It's a treacherous way to approach the playoffs and the Blues will have to regroup during the week and re-acquaint themselves with the bludgeon/rapier combination that has put them on top of the table.
They got the bludgeon bit right last night but there was no rapier, which they desperately needed against a supremely physical and unashamedly cynical Sharks side.
Cheap shots rained in during the second half and the Sharks even tried the outrageous tactic of substituting Johann Ackermann immediately after he was the lead protagonist in a spiteful dust-up with Sam Tuitupou in the hope of avoiding a yellow card.
But while the Blues could match the Sharks for intensity, especially when the All Blacks cavalry came off the bench for the final quarter, they couldn't when it came to accuracy and tactical execution. It was brutal, old-fashioned, heart on the sleeve football, where the big men squared off and said to hell with the pretty stuff.
The surface was too greasy for either set of backs to open up and there just wasn't the space for anyone to get their dancing shoes on, yet alone do a little number in them.
That suited the Sharks, who despite the rain, appeared to be very much in their element.
In Brisbane last week, they showed a creative side to their previously uninspiring selves. But the foundation stone of their campaign this season has been their defence.
Finally, after 11 years, the South African sides, and in particular the Sharks, have discovered the discipline to successfully operate a structured screen. Their defensive organisation was relentless and their ability to tackle and regroup put the Blues under enormous pressure.
They couldn't find a way through and no doubt coach David Nucifora watched on wondering how things might have been better for his side had Luke McAlister not been in the stands with a broken cheekbone.
It wasn't just McAlister's ability to create something from nothing that the Blues missed - it was the control and kicking game he would have offered from second receiver.
Tuitupou is a committed and explosive player and made some hard yards last night but the Blues needed field position and a No 12 who could boom the ball behind the Sharks and turn them.
Without that supplementary kicking option and Isa Nacewa strangely erratic in his own execution, the Sharks were given ample opportunity to build momentum from the back through solid counterattacking and accurate offensive kicking.
When Ben Atiga spilled a perfectly weighted Percy Montgomery bomb in the first half, the Sharks were able to pounce on the loose ball and get it wide to Odwa Ndungane, who had three juggles before he got it under control and cruised over.
A massive dropped goal by Francois Steyn a few minutes later extended the lead and when JP Pietersen pounced on a Flavell fumble, it never really felt like the Blues could find a way back.
They bashed away gallantly for the second 40 minutes and tries by Keven Mealamu, David Gibson and Daniel Braid brought them close. But only ever close enough to get a look at the cigar, never actually get their hands on it.
Blues 25 (K. Mealamu, D. Gibson, D Braid tries; I. Nacewa 2 pens, 2 cons) Sharks 32 (O. Ndungane, J. Pietersen (2) tries; P. Montgomery pen; F. Steyn 2 DG, con, pen)