He initially competed for Selfless Gaming and later joined the San Francisco Shock team prior to the Overwatch League's inaugural season in 2018.

After achieving rankings of second in North America and fifth in the world on Overwatch's competitive mode, Won received an opportunity to try out for Selfless Gaming, an esports team based in Georgia, United States.

Initially inclined to join the London Spitfire, Cloud9's Overwatch team, Won eventually reconsidered his decision after further discussions with NRG and his parents.

Despite a loss in that match with a score of 2–3,[4] Won quickly demonstrated his skills and solidified his status as one of the league's premier damage players.

[6][7] In July 2019, just before the final stage of the season, the league introduced a role lock system, requiring teams to adhere to a composition of two tanks, two supports, and two damage players.

[7][9] After a loss to the Atlanta Reign in the first round of the 2019 season playoffs, the San Francisco Shock made their way through the lower bracket to secure a spot in the 2019 Grand Finals.

[11] Following this Grand Finals win, Won and his San Francisco Shock teammate, Matthew "super" Delisi, appeared on The Tonight Show Starring Jimmy Fallon on October 7, 2019 to talk about their victory.

Joining forces with his San Francisco Shock teammates Matthew "super" Delisi and Grant "moth" Espe, Team USA showcased their prowess as they navigated through the competition, emerging victorious in every match they played.

[21][22] In the PAX Arena Invitational finals, a North American tournament, Won led all players in assists at 122 and ranked fourth in kills-per-round at 0.90.

[24] Won continued his winning streak by securing another tournament victory on August 2, as Sentinels triumphed over Team SoloMid at the 30Bomb Summer Cup final.

[25] During the Pop Flash tournament, the fourth and final North American Ignition Series event, Won delivered an outstanding performance in the group stage against Immortals, earning 402 Average Combat Score, 32 kills, and 11 first bloods.

[21] Won went on to achieve two more tournament victories with Sentinels, winning the JBL Quantum Cup in December 2020 and the Valorant Champions Tour North America Challengers One in February 2021.

[27] On May 17, 2021, Riot Games announced a competitive ruling stating that Won would remain suspended for a total of six months, with the suspension period ending on September 10, due to his alleged failure to fully cooperate with the investigation.