At the age of only 17, Alan Sobocinski represented Brazil in the rapid-fire pistol, 25 metres sport shooting event at the 1948 London Olympics, where he placed 56th. He had much better luck three years later at the 1951 Pan American Games, where he took silver in the team version of that event (with Adhaury Rocha, Pedro Simão, and the non-Olympian Ademar Onéssimo Faller) and bronze with the small-bore rifle squad (alongside Alberto Braga, Antônio Guimarães, and the non-Olympians Ernani Martins Neves and João Sobocinski). By career, he was a civil engineer.