Medals: 1 Gold, 1 Silver (2 Total)
Charles Mayer is the only boxer from the 1904 Olympics to have won a U.S. national championship in another year. After winning the Olympic middleweight championship in 1904, he added the 1905 AAU middleweight championship. Mayer fought in the heavyweight division in 1904 only to appease the crowd who wanted to see him fight the heavyweight champion, Sam Berger. Though outweighed by 22 lbs. (180-158), Mayer put up a good fight but lost by decision.
|1904 Summer||St. Louis||Boxing||Men's Middleweight||United States||USA||1||Gold|
|1904 Summer||St. Louis||Boxing||Men's Heavyweight||United States||USA||2||Silver|
|1904 Summer||St. Louis||Boxing||United States||USA||Final Round||Match 1/2||1||1904-09-22||Mayer (USA) , Spradley (USA)||referee stops contest||3||1:40|
|1904 Summer||St. Louis||Boxing||United States||USA||Final Round||Match 1/2||2||1904-09-22||Berger (USA) , Mayer (USA)|
|1904 Summer||St. Louis||Boxing||United States||USA||Semi-Finals||Match #2||1||1904-09-21||Mayer (USA)||bye|