Lee Jae-sung (; born 10 August 1992) is a South Korean professional footballer who plays as an attacking midfielder or winger for Bundesliga club Mainz 05 and the South Korea national team. Club career Jeonbuk Hyundai Motors Lee joined Jeonbuk Hyundai Motors in 2014 and made his debut in the 2014 AFC Champions League match against Yokohama F. Marinos on 26 February. Choi Kang-hee, the manager of Jeonbuk at the time, praised his ability which kept balance about attack and defense of team, and actively used him, the newcomer. In 2016, he spent his best season by providing 17 assists during a year and winning the 2016 AFC Champions League. In the 2017 K League 1, he won the Most Valuable Player award after having eight goals and ten assists during 28 appearances. Holstein Kiel In July 2018, Lee joined 2. Bundesliga club Holstein Kiel on a three-year deal until 30 June 2021. The transfer fee paid to Jeonbuk was reported as €1.5 million. He played his first game against Hamburger SV on 4 August, and was named the Player of the Matchday by leaving a deep impression with two assists. On 13 January 2021, he played full time and scored the fourth penalty in a 2020–21 DFB-Pokal match, where Kiel won 6–5 on penalties after drawing 2–2 against Bayern Munich. Afterwards, Kiel reached the semi-finals of DFB-Pokal for the first time in history, but they were eliminated by Borussia Dortmund. Kiel also finished third in the 2020–21 2. Bundesliga, qualifying for the promotion play-off. In the two-legged play-off, Lee scored a goal and provided an assist, contributing to all two of Kiel's goals, but they lost 5–2 on aggregate to Köln. Mainz 05 In July 2021, Lee joined Bundesliga club Mainz 05 on a three-year deal until 30 June 2024. International career In the 2017 EAFF Championship, Lee led South Korea's title, and was named the Most Valuable Player and the Best Duel Player. Lee was named in South Korea's squad for the 2018 FIFA World Cup, and played all three games in the group stage. He also participated in the 2022 FIFA World Cup, helping South Korea advance to the knockout stage. Career statistics Club International Scores and results list South Korea's goal tally first, score column indicates score after each Lee goal. Honours Jeonbuk Hyundai Motors K League 1: 2014, 2015, 2017 AFC Champions League: 2016 South