Jeong qualified for two swimming events at the 2004 Summer Olympics in Athens, by clearing FINA B-standard entry times of 54.91 (100 m butterfly) and 2:00.84 (200 m butterfly) from the Dong-A Swimming Tournament in Seoul.[5][6] In the 200 m butterfly, Jeong challenged seven other swimmers on the second heat, including Olympic veteran Vladan Marković of Serbia and Montenegro. He raced to second place in his heat and twenty-fourth overall by 0.84 of a second behind Canada's Nathaniel O'Brien in 2:00.96.[7][8] In the 100 m butterfly, Jeong blasted a new South Korean record of 54.79 to break a 55-second barrier and top the third heat. Jeong failed to advance into the semifinals, as he placed thirty-eighth overall out of 59 swimmers in the preliminaries.[9][10]
References
^ ab"수영국가대표 정두희를 말하다" [Meet the national swimmer Jeong Doo-hee] (in Korean). Young Hyundai. 10 September 2013. Archived from the original on 8 December 2015. Retrieved 3 December 2015.