Lee Jae-dong successfully advanced to the quarterfinals of the Google Play ASL Season 21 as the winner of Group C, following matches held at Freec Up Studio in Samseong-dong, Seoul, on the 20th. In Group C, which drew significant attention for featuring both Kim Taek-yong and Lee Young-ho, Lee Jae-dong played perfectly to secure his spot in the round of 8 first.

In the first match between Kim Taek-yong and Kim Tae-young, the outcome was unpredictable as it was a single-game format. Kim Taek-yong opened with a 1-gate double, while Kim Tae-young attempted a mine triple. Although Kim Taek-yong quickly identified this with his probe, he chose to match the expansion rather than go for an immediate attack.

Ultimately, Kim Tae-young executed his game plan well, successfully defending against a Reaver and building momentum. He moved out to the center with a supply count of around 150. It was a strong timing, as the Protoss had a similar supply count and Zealot leg speed (speed upgrade) had not yet finished. However, Kim Taek-yong bought time and, once his Zealot speed upgrade was complete, utilized a shuttle and High Templars to win a decisive battle and seize the lead.

Then came the 'Lee - Ssang - Rok' (Lee Young-ho vs. Lee Jae-dong) for the first time in 2,756 days. Lee Young-ho prepared a no-barracks double followed by a mechanical Terran build. Lee Jae-dong, having scouted the build, focused on maximizing drone production to keep pace, opting to secure more drones rather than rushing out Mutalisks.

Lee Young-ho played greedily, taking a quick triple expansion while simultaneously investing in upgrades at two Armories and Science Vessel upgrades. Lee Jae-dong prepared a Mutalisk-into-Hydralisk timing attack, striking just before the Terran Siege Tanks could reach Siege Mode, defeating Lee Young-ho and advancing to the winners' match.

In the winners' match between Lee Jae-dong and Kim Taek-yong, Lee Jae-dong prepared a 1-Hatchery Zergling/Lurker all-in on 'Jane-do,' a map considered favorable for Protoss. The strategy was flawless; the single Cannon was insufficient to hold it off, and Lee Jae-dong took the first set. The second set began with both players playing standard openings.

Lee Jae-dong produced a small number of Mutalisks and Scourge to force Kim Taek-yong to invest in Corsairs and Cannons, while he saturated his drones and prepared Hydralisks. After whittling down the Corsair count and forcing the High Templars to expend their energy, he used a large force of Hydralisks to surround and crush the Protoss army.

With the Zerg supply count over 30 higher, the Protoss was struggling, as the third expansion lacked gas, making it difficult to add more Templars. Although Kim Taek-yong defended well, he could not overcome the resource deficit. Lee Jae-dong eventually broke through the defense, winning 2-0 and becoming the first player to advance to the quarterfinals.