At this point , Villa had been in the American phase of his career for only 4 months .
Villa defeated Buff in an upset , knocking out the champion in the 11th round to win the American Flyweight Championship .
At this point , Villa had been in the American phase of Villa 's career for only 4 months .
Villa defeated Buff in an upset , knocking out the champion in the 11th round to win the American Flyweight Championship .