All Blacks flyhalf Dan Carter was unimpressed by his scratchy return in the number 10 shirt against Scotland but grateful just to get through the 24-16 win unscathed.

Starting at flyhalf for the first time in a year after a season blighted by a broken leg, Carter was well below his best at Murrayfield, struggling with handling errors particularly in the opening exchanges before being replaced shortly after halftime.

"That first 20 (minutes) was pretty scratchy and there were a lot of mistakes from me personally which, if I get another chance, I'll have to improve," Carter told reporters.

"My option-taking probably wasn't the best at times. But I was pretty pleased to be back out there playing again and I felt as the game went on I grew in confidence."

Carter was replaced by Colin Slade, rated fourth in the pecking order of New Zealand number 10s, with Beauden Barrett and Aaron Cruden having taken the reins in Carter's prolonged absence during the southern hemisphere Rugby Championship.

Slade, who started on the wing, proved an effective replacement, booting a second-half penalty to keep the All Blacks' noses in front and converting the winning try.

All Blacks assistant coach Ian Foster was not marking Carter too harshly.

"It just shows you how hard it is to come back in to test rugby and get up to speed quickly," he said. "It was just another box ticked for him."

After victories against the United States and England, the All Blacks will bid to finish their season-ending tour undefeated when they play Wales in Cardiff next weekend.