In Budapest Szokolyi immediately joined the Magyar Athletikai Club (MAC). Founded in 1875, MAC was the first athletics club in continental Europe and played a pioneer role in developing sports in Hungary. Competing in the junior category – athletes who did not participate in public competitions before were regarded as juniors –, Szokolyi won his first race in the 100 metres dash at the 1890 autumn championships of MAC. (That time MAC organized a spring and a autumn championships every year.) Szokolyi participated in the seniors' race as well, finishing third in the 100 yards.