The win over Polish Kamil Majchrzak is undoubtedly the biggest in Møller's career, as the young Dane has never qualified for a main ATP tournament.
Until now Moller has played in Challenger tournaments ranked just below.
It is still unknown who will be the opponent for Moller in the first round at the Madrid Open, but it is certain that the Dane could potentially meet Holger Rune in the third round if both players reach that stage of the tournament.
On Tuesday evening, Moller managed to qualify for the main draw of Madrid Open with a 5-7, 6-4, 6-4 win over Poland's Kamil Majchrzak.
Moller was ranked 24 places lower than his opponent, but managed to continue his great form from last week.
Last week, the 21-year-old Dane won his second Challenger tournament ever in Portugal which catapulted him into a position as 114 in the world.
Holger Rune also made a huge jump in the world rankings thanks his impressive tournament win over Carlos Alcaraz in Barcelona.
Rune is seeded eighth in Madrid and is therefore through to the second round. In his first match, he will face the winner of the match between Hungarian Fábián Marozsán and Italian Flavio Cobolli.