Moller, ranked 174th in the world, could not have dreamed of a better start to the crucial match.
The 23-year-old Dane broke his opponent's serve to take a 2–1 lead—converting his third break point—and proceeded to completely dominate the set.
Moller broke serve again to go up 4–1 and shortly thereafter served out the set, winning 6–2 on his first set point.
21-year-old Radulov, ranked 596th in the world, had shown glimpses of his talent during Friday's loss to Holger Rune, and he raised his level significantly at the start of the second set against Elmer Moller.
The Dane faced a setback when he was broken to fall behind 1–3; although Moller responded by breaking back to make it 2–3, Radulov maintained his momentum by breaking serve again to lead 4–2.
From that point on, Moller was simply the better player. He won the next four games and sealed the match with an ace, sparking celebrations.