At the 2017 World Masters, Ratajski was unseeded and had to start from the first round. He defeated two-time reigning champion Glen Durrant in the quarter-finals, Scotland's Cameron Menzies in the semi-final, and world number one Mark McGeeney 6–1 in the final for his first televised major title. In doing so, Ratajski also guaranteed qualification for the 2018 BDO World Darts Championship, but declined his invitation in favour of an attempt to qualify for the rival 2018 PDC World Darts Championship. He qualified for the latter as the top ranked Eastern European on the PDC Pro Tour.