He continued playing with De Ramblers until 1945, when on the request of conductor Dolf van der Linden, he became a trombonist and arranger for the new Metropole Orkest.
This passage describes a musician's career shift from playing with De Ramblers to becoming a trombonist and arranger for the Metropole Orkest, prompted by conductor Dolf van der Linden's request in 1945.