Question: What was the unofficial name of the event that caused the man who defeated the great John L. Sullivan to rescind his retirement after hearing of the outcome?
Sentence (from "James J. Corbett"): Despite a career spanning only 20 bouts, Corbett faced the best competition his era had to offer; squaring off with a total of 9 fighters who would later be enshrined alongside him in the International Boxing Hall of Fame.
Relevant evidence: No