Porzingis exits with sore hip in Knicks’ ugly loss

With Floyd Mayweather seated in the front row, the Nets put a beating on the Knicks that the boxing champion would’ve been proud of.

It was just preseason, and won’t count in the standings. But with Brooklyn coach Kenny Atkinson admitting their defense would have to carry them until their offense gets in sync, Sunday’s 117-83 rout of the Knicks showed what that could look like.

The Nets dominated defensively, turning over their rivals and running their way to a 38-point lead in front of 14,161 at Barclays Center.

The Knicks fell to 0-3 in the preseason with two games left, and lost star forward Kristaps Porzingis with a sore right hip. He had six points on 2-of-6 shooting and finished a…