Contested on the second day of the games, drenching rain made the track soggy and slow for the running of the 100 meter dash semi-finals. Despite the unfavorable conditions Osendarp still managed a time of 10.6, right behind American Ralph Metcalfe.
In the 100 meter final he ran a 10.5, behind Americans Jesse Owens 10.3, and Ralph Metcalfe 10.4.
At the Berlin Games was considered the best European in races dominated by African American sprinters. Upon his return home was called "the best white sprinter" by the Dutch press.
Basis for his future involvement in National Socialism was laid in Berlin. It was in Berlin that he first came under the influence of SS propaganda.