Logan Price was meant to be in the stands at Vector Arena on Saturday to watch UFC Fight Night 43 in Auckland.
But the featherweight will instead be part of the New Zealand team at the inaugural International Mixed Martial Arts Federation World Championships in Las Vegas next week.
The 26-year-old flies out on Saturday morning and the competition, which features amateur fighters from about 20 countries, starts on Monday.
"I just want to learn as much as I can," Price said. "We will take one fight at a time and not think about the finals."
Price, who used to play rugby, got into mixed martial arts after wanting to keep his weight down during the off season.