Complex sentence: The main contribuition of WAA to boxing was the creation of the 168 lbs division (junior light-heavyweight or super-middleweight) in April 1982, when Jerry Halstead knocking Ron Brown out in 6 rounds, in Denver, Colorado.
Split into simpler sentences: The main contribuition of WAA to boxing was the creation of the 168 lbs division (junior light-heavyweight or super-middleweight) in April 1982. The first champion was Jerry Halstead, who knocked Ron Brown out in 6 rounds, in Denver, Colorado.