Kaj Ramsteijn started at the age of 10 in the Feyenoord youth academy, coming over from DWO Zoetermeer.

Ramsteijn made his first goal in a match against Willem II on 27 November 2010.

After his first season at professional level, Ramsteijn was rewarded for his good season with a transfer to his former club Feyenoord, who has an extensive partnership agreement with Excelsior, together with team-mates Guyon Fernandez and Miquel Nelom.

In 2013, he was hired by Sparta Rotterdam[2] and a year prior to it signed a two-year contract with Feyenoord.

[3] This biographical article related to association football in the Netherlands, about a defender, is a stub.