On the 4th, Lee Jae-ho defeated Lee Jae-dong 3-2 in the quarterfinals of the AfreecaTV StarCraft League (ASL) Season 21, held at the FreecUp Studio in Daechi-dong, Seoul, to secure his spot in the semifinals.

On Match Point, Lee Jae-ho took his natural expansion, opened with one Factory and one Starport, and successfully defended against Mutalisks with Cloaked Wraiths. He then transitioned into a Bionic army with Science Vessels and launched a timing attack on Lee Jae-dong’s 11 o'clock expansion. By gaining the high ground by a split second, Lee Jae-ho won the engagement and took the first set.

In the second set on Jade, Lee Jae-ho again took his natural expansion and built two Starports for Wraiths. He consistently produced Wraiths to fend off Lee Jae-dong’s Mutalisks and transitioned to Bionic play earlier than expected to launch an attack. Lee Jae-dong prepared a Hydra-Lurker composition to counter the Terran push.

Lee Jae-dong successfully repelled the Terran army at his natural expansion and moved into the center with Defilers. He defended his front with Defilers while preparing a massive Hydra-Lurker drop. However, his natural expansion Hatchery was destroyed, though Lee Jae-dong managed to deal significant damage with a counter-drop into the Terran main base.

Since both players were on equal economic footing, the momentum favored the Terran. Lee Jae-dong held on with Defilers and superior ground upgrades, but he eventually reached his limit. As the supply gap widened, Lee Jae-ho closed out the set to make it 2-0.

In the third set, Lee Jae-ho attempted a 1-Factory Starport double. His early 2-Marine poke dealt minor damage, but Lee Jae-dong easily blocked the follow-up 2-Vulture attack. Lee Jae-dong committed heavily to Mutalisks and Scourge. Lee Jae-ho noticed this and built multiple Turrets in his main base.

Forced to attack, Lee Jae-dong’s Scourge-heavy play resulted in a net loss. Although he secured the 11 o'clock expansion quickly, his continuous Mutalisk production was essentially an all-in. However, a second wave of attacks caused significant damage to the Terran natural expansion, allowing him to produce Drones and transition into a macro game.

While Lee Jae-ho kept the pressure on with Wraiths, Bionic units, and Dropships, Lee Jae-dong defended well, and Lee Jae-ho’s economy was surprisingly thin. After securing an additional gas expansion at 12 o'clock and producing Ultralisks, Lee Jae-dong finally recorded his first win after two losses.

In the fourth set on Polarity, Lee Jae-ho opened with an 8-Barracks pressure build. He picked off two Drones, resulting in a favorable trade, and the game settled into a standard macro match. Lee Jae-dong secured his 7 o'clock expansion safely and added Defilers.

Lee Jae-ho responded by taking a third expansion and a 3 o'clock Command Center, opting for traditional Bionic play and Battlecruisers rather than Late-Game Mech. However, Lee Jae-dong secured four gas geysers and produced Ultralisks. Lee Jae-dong then turned the tables, pressured the Terran, and leveled the series at 2-2.

In the final fifth set, Lee Jae-ho opened with a Vulture double. This time, he prepared Valkyries instead of Wraiths. Rather than attacking recklessly with Mutalisks, Lee Jae-dong took the 12 o'clock expansion quickly and prepared for Lurkers. Lee Jae-ho needed to gain an advantage before Defilers appeared. Time was on Lee Jae-dong's side, but after building a Defiler Mound, he engaged in a war of attrition without Defilers, losing the 12 o'clock expansion and giving the Terran the advantage. Ultimately, Lee Jae-ho denied his opponent any chance to recover, defeating Lee Jae-dong 3-2 to advance to the semifinals.