Semi-finals. They then accepted an invitation to the NIT and then won the NIT. It is obvious the NCAA was the most prestigious because BYU went there first. In 1966 only conference champions were invited to the NCAA. Utah was the conference champion even though BYU beat them twice. Utah went to the final four and lost in the semi-final game. BYU was invited to the NIT when the failed to qualify for the NCAA. The played well and won the NIT. As explained here the NCAA was more prestigious than the NIT in both 1951 and 1966.