[2] In the Autumn of 2014, Busk was sent out on loan to fellow Superliga club AC Horsens, and the following year had a spell with Sandefjord.

[4] Busk made his debut for Sønderjyske on 11 August, coming on in the first half for the injured starter Nicolai Flø during a 2–0 league loss to his former club, Copenhagen.

This was Busk's first competitive appearance in over six years, with his last game being on 7 April 2018 for Union Berlin.

[5] On 1 February 2025, German Bundesliga side TSG Hoffenheim confirmed that they had signed Busk on a season-long loan deal to replace the club's goalkeeper, Oliver Baumann, who had suffered a serious injury.

This biographical article related to association football in Denmark, about a goalkeeper, is a stub.