However, Fox also said that while Savea had been struggling, he believed the Hurricanes winger would bounce back eventually and that this is only one rough period in his career.
In contrast, Fox had nothing but praise for first-five starter Beauden Barrett and centre George Moala.
He believed that Barrett's always had the potential to be an All Blacks starter, and his performance last night was of no surprise.
"We're just seeing the maturing of a player," Fox said.
"I mean, he's world class at what he does, there's no doubt, and he was outstanding last night."
Similarly, Fox said that George Moala had shown real promise during the All Blacks camp and he can be proud of what he did last night.