[3] He won a two-year PDC Tour Card in 2015 by defeating Prakash Jiwa 5–1 in the final round.

[6] He eliminated Steve Brown, Michael Smith, Ken MacNeil and Jelle Klaasen to reach his first PDC quarter-final at Players Championship 4 and lost 6–3 to Lewis.

In April, de Zwaan won his first PDC ranking title by beating Jonny Clayton 6–5 in the final of Players Championship 10.

De Zwaan reached the fourth round of the 2020 PDC World Championship, where he played Peter Wright.

In January 2023 De Zwaan won his Tour card straight back at Q-School, winning the second day.

[15][16] At the 2023 UK Open in March, De Zwaan reached the last 32 with wins over Lukas Wenig, Geert Nentjes, James Wilson and Danny Jansen.

In 2024 De Zwaan continued in his second year with Tour card and signed a multi-year contract with the company Unicorn.

[17] In the same time he continued battling with his injured shoulder and was forced to skip several tournaments due to a persistent bursitis problem.