DENVER - It was the kind of blow that occurs thousands of times in boxing matches across the country: In the third round of a women's bout, Becky Zerlentes took a shot to the head above her left eye, then staggered forward and fell to the canvas. Only this time, Zerlentes never regained consciousness and died, becoming the first female boxer to die in a sanctioned event. The death stunned those who knew Zerlentes, a 34-year-old college instructor remembered as a fun-loving, adventurous person who had a particular fondness for sports. "This is so much more than about boxing," said...