2021 ATP 250 Sofia Open - Marchenko win two players in the top ATP 100 players of the world rankings.
In qualifying where he started he won first match 6-3, 6-3 over ATP 83 Marco Cecchinato (semifinalist RG 2018) and current ATP 83 player. Next match Illya was stronger over Tomas Machac in hard match 3-6, 6-3, 7-6 and he enter to main draw.
In main draw Marchenko win Andeas Seppi 6-4, 6-2 current ATP 87 player. Second round he lost very strong opponent John Millman ATP 48 .
Marchenko's Gear :
String : Mayami Magic Twist