split decision

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A decision declaring the winner of a boxing match in which the judges and referee are not unanimous in their opinions.

Wiktionary

1. n. an outcome in several full-contact combat sports where two of the three judges score for the same fighter as the winner, while the third judge scores for the other fighter.

WordNet 3.0

1. n. a boxing decision in which the judges are not unanimous