Freeman completed just 37% of his passes and looked out of sync with his receivers after being thrown into the game for his first start just two weeks after joining the club.
"If I had to do it over again," Frazier told reporters. "I don't think I would do it any differently.
"There was nothing I look back at that week in preparation that would have indicated that we would have come up with zero points from an offensive standpoint.
"One of my concerns was how he'd be able to get information in the huddle, relay plays at the line of scrimmage. We didn't have any mental errors in that area. It was more mechanical things."
The Vikings are 1-5 in their season following their defeat to the Giants.