The Blues paid for an act of indiscipline by captain Dalton Papali'i as the Crusaders won a brutal Super Rugby Pacific showdown 15-3 in Christchurch on Saturday.
The defending champions made it two wins from two over the Blues, who they also beat in last year's final, but the tense contest was in stark contrast to the thrilling 34-28 victory in round three.
Up 10-3 at halftime, the Crusaders took command soon after the interval when All Blacks flanker Papali'i was shown a yellow card for a late and high tackle on his New Zealand teammate, fly-half Richie Mo'unga.
Crusaders winger Leicester Fainga'anuku crossed in the left corner from the same play.
Papali'i's offence was subsequently upgraded to a red card by the television match official and his under-manned team rarely threatened for the remainder.
The result left the Crusaders third in the table and the Blues fifth with both on course for next month's finals.
Crusaders coach Scott Robertson was delighted to restrict opponents laden with All Blacks to just three points – equalling the Blues' lowest points return from any competition match in their history.
"Winning was off the back of a lot of carrying the ball," Robertson said.
"We didn't want to do too much defending, we wanted to make them tackle and they did."
Blues fly-half Beauden Barrett conceded the home side were more clinical.
"They took their opportunities, there weren't many in that game.
"When we sped the ball up in the second half, we started to see some opportunities but we weren't good enough to finish," the All Blacks test playmaker added.
Of concern for the Crusaders and All Blacks was the early departure of test prop Joe Moody with an ankle injury.
Moody, 34, has endured a dreadful run with injuries since the 2019 World Cup.
He was unable to add to his 57 tests last year after rupturing knee ligaments.
The Crusaders have already lost two other test props – George Bower and Fletcher Newell – to season-ending injuries.
Fainga'anuku enhanced his growing test claims with a powerhouse display.
Playing his 50th match for the Crusaders, he took his try tally for the season to 10, sitting level with Chiefs speedster Shaun Stevenson at the top of that list.
The Hurricanes are second after an 11-try romp in a 71-22 home win over the Moana Pasifika earlier.