Plans for a profitable hit and run mission to Sydney turned ugly for the Blues as they fell to a final minute penalty.
In oppressive conditions, the Blues watched a 24-10 lead ebb away yesterday as they made repeated mistakes until lock Culum Retallick was ruled offside at a late ruck and Waratahs five eighths Bernard Foley goaled the pressure kick.
Flaws at the start then the conclusion told on the Blues who had regathered momentum through the middle stages and looked as though they would reverse their recent troubles.
"Just individually we had too many mistakes and could not apply pressure over the distance of time," captain Ali Williams said.
"Sometimes you think it can just happen but we have got to get back to the basics."
The omens were not favourable at the start. The weather in Sydney was brutally humid and when the Waratahs scored early from a training ground move, the Blues looked as if they were jetlagged, sleepy or suffering from sunstroke.
They needed something special to ignite them. Hooker James Parsons provided the trigger when he collected a try which would have been the envy of franchise legends Sean Fitzpatrick and Keven Mealamu.
Parsons' lineout throw went awry but it was not as costly as the Waratahs slapdown. The bounce eluded everyone except the marauding Parsons who collected, ran 35m then bounced his way to the tryline through two defenders.
When Brendan McKibbin goaled a penalty the sides were locked at 10-all and referee Francisco Pastrana decided they all needed a quartertime water break, to the public disgust of Waratahs coach Michael Cheika.
He was fuming even more at the break as the Blues had gathered two unanswered converted tries through the Waratahs' neglect as much as the Blues enterprise.
The best period of Blues attack finally created some mismatches on defence and five eighths Chris Noakes was able to beat the defending tight forwards to squeeze across the line and convert his try.
That improvement went up a notch when a strong kick chase from George Moala harassed the defence and he managed to flip a pass up to fullback Charles Piutau who had trailed the action.
What had been an armwrestle looked like a match moving quickly out of the Waratahs grasp.
They regrouped however after the interval and while errors littered the second half as the ball became more slippery, the Waratahs made less gaffes than the Blues.
League convert Israel Folau latched onto a try after a nifty break from his inside backs helped by a forward pass. Five eighths Bernard Foley had taken over the goalkicking and also sliced through for a try against some tiring defenders.
He went one better with a great sideline penalty from a foolish Blues mistake but that effort was soon equalled by the calm Noakes.
With five minutes left Foalu should have iced the game when he raced 60m but Piutau shadowed him hard enough to force theWaratahs fullback into a foolish offload and that threat passed.
But the danger had not lifted as the Blues were pinned down in their half and when Retallick nudged round the side of a ruck too early, the stalemate was broken.
Blues 27 (James Parsons, Chris Noakes, Charles Piutau, tries; Chris Noakes 3 con, 2 pen)
Waratahs 30 (Drew Mitchell, Israel Folau, Bernard Foley, tries; Brendan McKibbin con, pen, Bernard Foley 2 con, 2 pen) Halftime: 24-10