In 1913, Muller competed against fellow Irish American Athletic Club member and nine time Olympic medalist Martin Sheridan in the discus throw at the New York Metropolitan Association championship meet of the Amateur Athletic Union.[3] Sheridan, who won four Olympic gold medals for throwing the discus (both Greek and Free style), came out of retirement from athletics to compete in this event,[4] but was defeated by Muller who hurled the discus 133 feet, or 5 feet 6.5 inches further than Sheridan. (Martin Sheridan's brother Andrew J. Sheridan, also of the Irish American Athletic Club, came in 3rd place).
^"Winged Fist Wins Metropolitan Title - Defeats New York A.C. by 74 to 68." New York Times, Sept. 21, 1913.
^"Pick of Champions Entered for Titles - The Metropolitan Association Sports at Travers Island Promise Keen Competition." New York Times, Sept. 14, 1913.