1. Early Life and Youth Career
Oh Jae-suk's football journey began in his hometown, leading him through a structured youth development system that prepared him for a professional career. His early education and youth club affiliations laid the groundwork for his future success.
1.1. Early Education and Youth Club Career
Oh Jae-suk was born on January 4, 1990, in Uijeongbu, Gyeonggi Province, South Korea. He developed his football skills during his formative years at Shin-Gal High School from 2005 to 2007. Following high school, he continued his development at Kyung Hee University from 2008 to 2009, further refining his abilities before turning professional.
1.2. Youth National Teams
Oh Jae-suk was a prominent figure in South Korea's youth national teams, participating in various age-group squads and major international tournaments. He represented the South Korea U-17 team at the 2007 FIFA U-17 World Cup. In 2008, he played for the U-19 national team at the AFC U-19 Championship, where the team secured a third-place finish, earning a spot in the subsequent FIFA U-20 World Cup. Oh then went on to compete in the 2009 FIFA U-20 World Cup held in Egypt. His consistent performance at the youth level also saw him called up to the U-21 and U-22 squads. He later became a key player for the U-23 Olympic team.
2. Club Career
Oh Jae-suk's professional club career began in South Korea before he moved to Japan, where he achieved significant success, and later returned to the K League.
2.1. Suwon Samsung Bluewings and Gangwon FC
Oh Jae-suk started his professional career in 2010 after being selected as the first-round pick in the 2010 K League Draft by Suwon Samsung Bluewings. He made his professional debut on March 6, 2010, in a 4-3 home victory against Busan IPark, a performance that reportedly satisfied then-coach Cha Bum-kun. In his debut season, he made 5 league appearances and contributed to Suwon's FA Cup victory.
In 2011, he was loaned to Gangwon FC for the majority of the season. He made his debut for Gangwon on March 5, 2011, against Gyeongnam FC and scored his first professional goal on October 1, 2011, in a home match against Jeonnam Dragons at Chuncheon Stadium. During his loan spell, he played 22 league matches and scored once. Although Gangwon finished 16th and last in the K League standings that year, they managed to retain their league status due to the absence of relegation that season.
His performances led to a permanent transfer to Gangwon FC in 2012, as part of a trade involving Kwak Kwang-seon plus cash. Before the 2012 London Olympics, there were reports of a potential transfer to Gamba Osaka, but Gangwon FC's newly appointed coach, Kim Hak-bum, blocked the move, stating he would not transfer a valuable player for an unreasonable price. In 2012, Oh made 31 league appearances, scoring twice, helping Gangwon to a 14th-place finish, just above the relegation zone.
2.2. Gamba Osaka
In 2013, Oh Jae-suk joined Gamba Osaka, which had been relegated to the J2 League the previous season. His decision to move to Japan was initially met with reluctance, partly due to the financial difficulties faced by his former club, Gangwon FC, which reportedly owed two months of salary. However, upon consulting with Ikeda Seigo, the physical coach for the U-23 Korean national team, Oh was advised that "it will definitely be tough if you go (to Japan). But if you overcome that difficulty, your life will change." This advice ultimately convinced him to make the move.
His first year at Gamba Osaka saw limited playing time, largely as a reserve behind veteran right-back Akira Kaji, and he made only 5 appearances as Gamba won the J2 League and secured promotion back to the J1 League.
The 2014 season marked a significant turning point for Oh Jae-suk and Gamba Osaka. With Kaji's departure to America before the season, Oh found himself in competition with newly acquired Koki Yonekura for the right-back position and Hiroki Fujiharu for the left-back slot. Due to a demanding schedule, coach Kenta Hasegawa rotated these players, and Oh became a regular, often playing both right and left full-back. He played a crucial role in Gamba's historic domestic treble, winning the J1 League title, the J.League Cup, and the Emperor's Cup. He made a total of 37 appearances across all competitions that year.
In 2015, Gamba Osaka continued its success, retaining the Emperor's Cup and adding the Japanese Super Cup to their trophy cabinet. They also reached the semi-finals of the 2015 AFC Champions League before being defeated by Chinese club Guangzhou Evergrande over two legs. Despite these team achievements, Oh's playing time decreased as Yonekura and Fujiharu solidified their starting positions. He featured only 10 times in the league and 22 games overall. In a controversial incident during the J.League Championship final first leg against Sanfrecce Hiroshima on December 2, 2015, Oh was shown a straight red card in the 86th minute for "rough play" while Gamba led 2-1. His team subsequently conceded two goals in injury time, losing 3-2, and ultimately suffered a 4-3 aggregate defeat. Oh was suspended for the second leg due to the red card.
From 2016 to 2018, Gamba Osaka did not win any trophies, but Oh continued to feature regularly despite stiff competition from Yonekura, Fujiharu, and the emerging Ryo Hatsuse. He made 18, 29, and 24 league appearances in the 2016, 2017, and 2018 seasons, respectively, as Gamba finished 4th, 10th, and 9th. He played 8 league games and 4 League Cup matches for Gamba in the first half of 2019.
2.3. Loan to FC Tokyo and Transfer to Nagoya Grampus
On July 8, 2019, Oh Jae-suk was loaned to fellow J1 League club FC Tokyo until the end of the season. He made 12 league appearances during his temporary spell there.
He returned to Gamba Osaka for the start of the 2020 season but on July 9, 2020, he made a permanent transfer to Nagoya Grampus. He was assigned jersey number 34. For Nagoya, he played 22 league matches and 1 League Cup match.
2.4. Return to K League (Incheon United and Daejeon Hana Citizen)
In 2021, Oh Jae-suk returned to the K League after nine years, signing a permanent deal with Incheon United. He made 26 league appearances in his first season back. In 2022, he suffered from muscle-related injuries, which limited his league appearances to just 3 matches, though he featured in 3 of the 5 championship playoff games.
In 2023, Oh Jae-suk was part of a trade involving defender Kwon Han-jin and moved to Daejeon Hana Citizen. For Daejeon, he played 22 league matches and 3 Cup matches in his first season.
3. International Career
Oh Jae-suk has represented South Korea at various levels, notably contributing to an Olympic medal and making appearances for the senior national team.
3.1. Olympic National Team
Oh Jae-suk played a crucial role for the South Korean Olympic football team. He participated in the 2010 Asian Games in Guangzhou, where the team earned a bronze medal. He was subsequently included in the final squad for the 2012 London Olympics. While initially expected to be a backup to Kim Chang-soo at right-back, Oh stepped up significantly after Kim suffered an injury during the quarter-final match against Great Britain. His subsequent strong performances contributed greatly to South Korea's historic bronze medal victory at the Olympics. As a result of this achievement, Oh Jae-suk was exempted from mandatory military service.

3.2. Senior National Team
Oh Jae-suk received his first call-up to the senior South Korea national football team in March 2016 for the 2018 FIFA World Cup qualifiers against Lebanon and Thailand. However, he had to withdraw due to a left foot injury sustained in an AFC Champions League match against Shanghai SIPG and was replaced by Kim Chang-soo.
He was re-selected for the national squad in August 2016 for the World Cup qualifiers. Oh Jae-suk made his A-match debut for South Korea on September 1, 2016, in a World Cup qualifier against China, where he played as a left-back. Between 2016 and 2017, he earned a total of 4 international A-match caps for the senior national team.
4. Personal Life and Episodes
Oh Jae-suk's personal life has seen him form significant relationships, engage with the public, and participate in notable humanitarian efforts, along with his marriage.
4.1. Influential Relationships
Oh Jae-suk's transfer to Gamba Osaka in 2013 was initially a difficult decision for him, partly due to the financial struggles of his previous club, Gangwon FC, which was reportedly two months behind on salary payments. He felt compelled to move to help his club financially, even though he was not enthusiastic about leaving. He sought advice from Ikeda Seigo, who was then the physical coach for the U-23 Korean national team. Ikeda told him, "It will definitely be tough if you go (to Japan). But if you overcome that difficulty, your life will change." This counsel ultimately influenced his decision to accept the transfer.
Upon his arrival at Gamba, Oh Jae-suk's initial attitude was reportedly negative, likely due to injuries and limited playing opportunities. He was known for being the last to arrive at practice and the first to leave, rarely watching first-team matches, and often checking Korean entertainment news on his tablet. Concerned by this behavior, his parents visited him in Japan and strongly reprimanded him, stating that his actions were unprofessional and could negatively impact future Korean players in Japan. Following this intervention, Oh Jae-suk significantly changed his routine, becoming the second earliest to arrive at practice and the latest to leave, though he admits he could never arrive earlier than his teammate Akira Kaji.
Akira Kaji, a direct rival for the same defensive position, became an invaluable mentor and friend to Oh Jae-suk. Despite their on-field competition, Kaji consistently supported Oh. He invited Oh to his home for a barbecue party to help him socialize with teammates, recommended his hair salon when Oh needed a haircut, and even hosted Oh's parents at his restaurant during their visit. Oh Jae-suk deeply respects Kaji, calling him an "unforgettable person." This admiration was further symbolized by Oh's decision to wear jersey number 22 at Gamba Osaka from 2014 onwards, positioned next to Kaji's number 21.
4.2. Public Interactions and Humanitarian Deeds
Oh Jae-suk was involved in a past misunderstanding concerning social media comments following the 2010 Asian Games. A post he made on his mini-hompy (a South Korean social media platform) was widely misinterpreted by netizens as a criticism of the Korean national baseball team, leading to public backlash. Oh later clarified that his comments were, in fact, aimed at the Japan national football team, not the baseball team.
In 2017, Oh Jae-suk demonstrated his humanitarian spirit by assisting a Korean woman undergoing treatment for a rare lung disease at the National Cerebral and Cardiovascular Center in Suita, Osaka, Japan. He reportedly offered to help because he understood the difficulties of adapting to a new country with language and cultural differences, especially while ill. He assisted with hospital admission procedures by interpreting for her and provided personal support by bringing her Korean food like kimchi, as well as a tablet loaded with Korean movies and dramas.
He is fluent in Japanese and can even speak the Kansai dialect, which he often uses in conversations with his Japanese teammates. While on loan at FC Tokyo, he appeared in a promotional video for a match alongside former Gamba Osaka teammate Kotaro Omori, speaking in the Kansai dialect.
4.3. Marriage
Oh Jae-suk announced his marriage on March 2, 2022, through his social media channels.
5. Career Statistics
Oh Jae-suk has accumulated extensive playing statistics throughout his club and international career.
5.1. Club Statistics
| Club | Season | League | Cup | League Cup | Continental | Other1 | Total | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Division | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | ||
| Suwon Samsung Bluewings | 2010 | K League 1 | 5 | 0 | 3 | 0 | 2 | 0 | 2 | 0 | - | 12 | 0 | |
| Gangwon FC (loan) | 2011 | K League 1 | 22 | 1 | 3 | 0 | 2 | 0 | - | - | 27 | 1 | ||
| Gangwon FC | 2012 | 31 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | - | 31 | 2 | ||
| Total | 53 | 3 | 3 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 58 | 3 | ||
| Gamba Osaka | 2013 | J2 League | 5 | 0 | 0 | 0 | - | - | - | 5 | 0 | |||
| Gamba Osaka | 2014 | J1 League | 24 | 0 | 3 | 0 | 10 | 0 | - | - | 37 | 0 | ||
| Gamba Osaka | 2015 | 10 | 0 | 1 | 0 | 3 | 0 | 4 | 0 | 4 | 0 | 22 | 0 | |
| Gamba Osaka | 2016 | 18 | 0 | 2 | 0 | 0 | 0 | 4 | 0 | 1 | 0 | 25 | 0 | |
| Gamba Osaka | 2017 | 29 | 0 | 1 | 0 | 2 | 0 | 7 | 0 | - | 39 | 0 | ||
| Gamba Osaka | 2018 | 24 | 0 | 1 | 0 | 7 | 0 | - | - | 32 | 0 | |||
| Gamba Osaka | 2019 | 8 | 0 | 0 | 0 | 4 | 0 | - | - | 12 | 0 | |||
| Gamba Osaka | 2020 | 1 | 0 | 0 | 0 | 0 | 0 | - | - | 1 | 0 | |||
| Total | 119 | 0 | 8 | 0 | 26 | 0 | 15 | 0 | 5 | 0 | 173 | 0 | ||
| FC Tokyo (loan) | 2019 | J1 League | 12 | 0 | 0 | 0 | 0 | 0 | - | - | 12 | 0 | ||
| Nagoya Grampus | 2020 | J1 League | 22 | 0 | - | 1 | 0 | - | - | 23 | 0 | |||
| Incheon United | 2021 | K League 1 | 26 | 0 | 0 | 0 | - | - | - | 26 | 0 | |||
| Incheon United | 2022 | 3 | 0 | 1 | 0 | - | - | - | 4 | 0 | ||||
| Total | 29 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 30 | 0 | ||
| Daejeon Hana Citizen | 2023 | K League 1 | 22 | 0 | 3 | 0 | - | - | - | 25 | 0 | |||
| Career total | 262 | 3 | 18 | 0 | 31 | 0 | 17 | 0 | 5 | 0 | 333 | 3 | ||
1 includes J.League Championship, Japanese Super Cup and Suruga Bank Championship appearances.
5.2. Reserve Team Statistics
| Club performance | League | Total | ||||
|---|---|---|---|---|---|---|
| Season | Club | League | Apps | Goals | Apps | Goals |
| Japan | League | Total | ||||
| 2016 | Gamba Osaka U-23 | J3 | 2 | 0 | 2 | 0 |
| Career total | 2 | 0 | 2 | 0 | ||
5.3. International Appearances
| Year | A-match | Youth National Teams | ||
|---|---|---|---|---|
| Apps | Goals | Apps | Goals | |
| 2007 | 0 | 0 | U-17 | (2007 FIFA U-17 World Cup) |
| 2008 | 0 | 0 | U-19 | (AFC U-19 Championship) |
| 2009 | 0 | 0 | U-20 | (2009 FIFA U-20 World Cup) |
| 2010 | 0 | 0 | U-23 | (Asian Games) |
| 2011 | 0 | 0 | 0 | 0 |
| 2012 | 0 | 0 | U-23 | (London Olympics) |
| 2013 | 0 | 0 | 0 | 0 |
| 2014 | 0 | 0 | 0 | 0 |
| 2015 | 0 | 0 | 0 | 0 |
| 2016 | 3 | 0 | 0 | 0 |
| 2017 | 1 | 0 | 0 | 0 |
| Total | 4 | 0 | (Youth team statistics are combined based on available data) | |
6. Honors
Oh Jae-suk has earned several team titles throughout his professional career in both South Korea and Japan.
Suwon Samsung Bluewings
- Korean FA Cup: 2010
Gamba Osaka
- J2 League: 2013
- J1 League: 2014
- J.League Cup: 2014
- Emperor's Cup: 2014, 2015
- Japanese Super Cup: 2015
South Korea U-23
- Asian Games Bronze Medal: 2010
- Olympic Games Bronze Medal: 2012