The unfancied Blues are two from two and have the maximum 10 points in Super Rugby after beating the Crusaders 34-15 at Eden Park.
The Blues scored five tries to none and led 20-6 at half-time, with giant right wing Frank Halai crossing twice for the second time in two matches, while blindside flanker Steven Luatua opening the scoring.
Luke Braid dotted down first after the break while left wing George Moala finished the scoring late in the game.
The Crusaders were extremely rusty after a first-round bye, uncertain under the high ball and - with New Zealand captain Richie McCaw on a six-month sabbatical - uncharacteristically vulnerable at the breakdown.
Crusaders captain Kieran Read's ruing a late video referee decision against his team that ruled out what looked a possible try to left wing Israel Dagg.
The Crusaders trailed by 12 points and were pressing hard with about 10 minutes to go, the Blues holding up two would-be tryscorers before Dagg crossed - but it was controversially ruled a double movement.
The tackler was man of the match Rene Ranger, who reinforced his early season claims to an All Blacks centre jersey, also adding two linebreaks which led to the first Halai try and the crucial Braid try after half-time.
It is the Blues' second bonus point win following a first-round victory in Wellington last week and firmly places Sir John Kirwin's side among the contenders for a title they have not won wince 2003.