Barrett's touchdown came after a display of some sublime attacking skills in a 100m dash while Smith's try ended nearly four minutes of lung-busting defence and discipline on their own line, which broke the French nerve.
At that stage France were still only 10-0 adrift after existing on 20 per cent first-half possession. On the resumption they turned up the flame. It was a pivotal time in the test.
The All Blacks held their composure to repel an incredible 26 phases.
As the forwards bashed away, the French backline got more twitchy about their involvement until halfback Maxime Machenaud fired a pass back to Frederic Michalak in the pocket. Michalak has plenty of skill but his instincts do not always cope best with defence.
Cue Saturday when Sam Cane charged down his dropped goal attempt before Michalak withered as he tried to retrieve the situation.
Ma'a Nonu reclaimed the ball, Aaron Smith fired out another sharp pass to Dane Coles, who found Julian Savea snorting up an inside channel to unload to Ben Smith.
In 23 devastating seconds on top of their exceptional defence, the All Blacks had turned pressure into profit and the Dave Gallaher trophy settled back into its holder.
The icing came very late through Barrett.
Debate will continue about the order of merit for the All Black tries.
