He then won the unranked Spring Cup, beating Vincent van der Voort in the semi-finals and then defeating Erik Clarys in the final.

After reaching the quarter-finals of the 2004 Finnish Open, Brantjes retained the Spring Cup title, beating Mario Robbe and Dick van Dijk before defeating Niels de Ruiter in the final.

He beat compatriot Co Stompé 3–2 in the first round, making a 170 checkout in only his second leg of the match, and then upset the previous year's runner-up and world number one, Mervyn King, again by 3–2.

Brantjes reached the second round of the 2005 International Darts League, winning his opening group games against van der Voort and Davy Richardson to qualify before losing to John Walton who won the group.

Brantjes has not played in a tournament since the 2006 World Masters where he lost in the very first round to Ireland's James Keogh.