In 1909, at the Amateur Athletic Union (AAU) metropolitan senior championships, held at Travers Island, Rosenberger took first place in 100 and 220 yard dash.[4] The following week, Rosenberger was part of the Irish American Athletic Club's four-man relay team that broke the world's record for the one-mile relay with a time of 3 minutes 20 2/5 seconds. The other three men on the record-breaking team were C.S. Cassara, Melvin Sheppard, and William Robbins.[5]
On April 9, 1911,[6] Rosenberger anchored the Irish American Athletic Club 4×440 yard relay team that broke the world record at Celtic Park, Queens, New York and set the first IAAF- recognized world record for 4×440 yard or 4×400 meter relay race, in time of 3 minutes and 18.2 seconds. The other members of the world record-setting team were Harry Gissing, Mel Sheppard and Harry Schaaf.[7]
Rosenberger participated in the 1912 Summer Olympics but was eliminated in a 400 m semifinal.[1] Next year, he competed in Australia with the AAU team,[8] and in 1915, he became the coach for the Long Island Athletic Club.[9]
Sullivan, James E. (1912). The Olympic Games Stockholm – 1912(PDF). New York: American Sports Publishing Company. Archived from the original(PDF) on April 10, 2008. Retrieved January 3, 2009.
