Ji-hun won the 2003 Ongamenet Starleague and the World Cyber Games 2004 grand final.

He first played StarCraft on a professional level during the 2001 Summer OSL Qualifiers.

In the 2005 EVER OnGameNet StarLeague he was seen as a veteran who had the potential to win the title, but came in third place.

[3] In February 2009 he started to serve his mandatory two year service for the Republic of Korea Air Force.

In 2010 he was asked to go to Korean Air's main hangar to watch the OSL, along with all of the other past winners, and accepted.