Chung Hyeon, South Korea's highest-ranked male tennis player, came up short of winning his third straight tournament on a second-tier tour on Sunday.
The 69th-ranked Chung lost to Go Soeda of Japan 3-6, 6-3, 6-3, in the final of the Seoul Open on the ATP Challenger Tour.
Chung, 18, had won two previous Challenger Tour events in Savannah and Busan. The loss snapped Chung's winning streak at 14.
Chung claimed the hard-fought first set before dropping the next two. He battled Lu Yen-Hsun of Chinese Taipei for two hours and 25 minutes in Saturday's semifinals.
Soeda, who reached No. 47 in 2012, has beaten Chung twice in their three meetings.
Chung, the 2014 Asian Games gold medalist in the men's doubles, reached No. 88 on the rankings to crack the top 100 for the first time last month, and has since soared to No. 69.
Lee Hyung-taik holds the record for the highest world ranking position for a South Korean player at No. 36 in August 2007.
Chung is slated to enter the qualifiers of the French Open, the season's second major, this week. He has also qualified for Wimbledon, the next Grand Slam tournament scheduled for June. (Yonhap)