Mezue ahịrịokwu na-esonụ: Maka 2012 Summer Olympics, A na-ewere Sun dị ka ọkacha mmasị na 400 mita na
1500 mita freestyle, nakwa onye na-azọ ọkwa na 200 mita freestyle. N'ihe omume mbụ ya, 400 mita freestyle, ọ meriri nrite ọla edo na oge nke 3:40.14, na-agbasa ihe ndekọ Olympic nke Ian Thorpe nwere na mbụ wee bụrụ nwoke mbụ na-egwu mmiri nwoke China iji merie nrite ọla edo na Olympics. Oge ya bụkwa nke atọ kachasị ọsọ n'akụkọ ihe mere eme, 0.07 sekọnd dị anya site na ndekọ ụwa, ma setịpụkwa ihe ndekọ ọhụrụ nke Asia. Mgbe otu ụbọchị nke mgbake gasịrị, Sun gbara ọsọ na mita 200 n'ụdị nnwere onwe. O meriri ọlaọcha na ngwụcha, na-ejikọ Park Tae-hwan na oge nke 1:44.93, ihe ndekọ mba ọhụrụ. N'echi ya, Sun gbara ụkwụ arịlịka n'ọsọ 4 × 200 mita n'ụdị nnwere onwe iji nyere ndị otu China aka inweta ọla nchara, ọla mbụ nke China na asọmpi nnwere onwe ụmụ nwoke.