Mezue ahịrịokwu na-esonụ: O'Neill bụ onye mmeri NCAA ugboro atọ na mgbanaka, na-emeri na 1987, 1988, na 1989, yana ijide ihe ndekọ kachasị elu (9.93) na 1987 na 1989. Mgbe ọ gụsịrị kọleji, ọ gara asọmpi mba ụwa. O'Neill bịara nke anọ na 1992 World Artistic Gymnastics Championships, nke kachasị elu nke ndị America, wee bụrụ nwoke mbụ America iji merie nrite na asọmpi ụwa na afọ 15 mgbe o meriri ọlaọcha na mgbaaka ụmụ nwoke na
1994 World Artistic Gymnastics Championships na Brisbane.