Grethen placed 5th in the men’s 1500m, with a time of 3:36.75, at the Golden Spike 2021 competition.

The World Athletics-sanctioned event was held in Ostrava, in the Czech Republic, on 19 May. The winner was Marcin Lewandowski of Poland, with a time of 3:35.57.

The Luxembourg Athletics Federation (FLA) said that Grethen beat his own previous outdoor record of 3:39.02, set in 2017.

According to the FLA, Grethen “collected important points” on Wednesday, which could qualify him for the Tokyo Olympic Games. He will automatically qualify if he runs the 1500m in 3:35.00 or less in an upcoming competition.

Grethen represented the grand duchy in the 2016 Rio Olympic Games.