2011: Was the medalist at the Springfield, OH, U.S. Open qualifier, shooting rounds of 66-66. Finished at 2-over for the week at Congressional CC to T30, improving on his first U.S. Open appearance (2010), when he qualified in similar fashion and went on to T40.

Has played in three other PGA TOUR events. He lost in the first round at the World Golf Championships-Accenture Match Play Championship, was 59th at the World Golf Championships-Cadillac Championship and missed the cut at the Memorial Tournament.

Has a trio of top-10 performances on the European Tour—a T6 at the Volvo Golf Champions, a T9 at the Volvo World Match Play Championship and a solo sixth at the Nordea Masters.

Battled fellow countryman K.J. Choi at the Asian Tour-Korean Tour co-sanctioned CJ Invitational in October in South Korea. Trailed Anthony Kim by five strokes entering the final round at Haesley Nine Bridges GC. Did his part by shooting a final-round 66 but fell by two strokes to a hard-charging Choi, who finished with a 67 to win by two strokes.

In December, he shot a third-round 64 at PGA West in Palm Springs, CA, to earn T3 honors at the PGA TOUR Qualifying Tournament. 2010: Made five PGA TOUR starts, with his top finish coming at the PGA Championship at Whistling Straits, where he T28. Burst on the scene with some dominant international play, winning for the second time as a professional, capturing the Maybank Malysian Open in Kuala Lumpur by a stroke over fellow countryman K.J. Choi. The win made him the second-youngest European Tour winner in history. at 18 years, 282 days, he was 69 days older than fellow Korean Danny Lee (Johnnie Walker Classic). Matteo Manassero took over the top spot with his victory in 2010.

He added top-10 finishes in four other international events. Was runner-up to Padraig Harrington at the Iskandar Johor Open at Horizon Hills G&CC in Malaysia, and added a T4 at the European Tour's Ballentine's Championship, a solo fourth at the Omega European Masters and a T8 at the Japan Golf Tour's Asia-Pacific Panasonic Open, his second consecutive top-10 in that event. His stellar play gave him the Asian Tour order of merit title, making him the youngest winner of that honor in the circuit's history. 2009: He had six top-10s around the world. His best Asian Tour performance was a T5 at the Worldwide Selangor Masters in Petaling Jaya, Malaysia. Was T9 at the Asia-Pacific Panasonic Open. 2008: Joined the Asian Tour as a 16-year-old and earned Asian Tour Rookie of the Year honors, thanks to his victory at the Midea China Classic, where he shot a final-round, 3-under 68 to edge Australian Terry Pilkadaris. His victory made him the third-youngest Asian Tour winner in history.

Began playing the sport at age 7. His dad bought him a junior set. He hit balls on the beach near his home in Seoul before school and then spend hours at the driving range after his studies were over for the day. Also played tennis, soccer and baseball before turning his sole attention to golf.

Attended Kyung-gi High School in Seoul.

Never travels without iPad and favorite Web site is twitter.com. Favorite pro team is Manchester United. Favorite show is "Unlimited Challenge," a popular program in South Korea.