Jonathans made her debut at the Olympics in the 2000 Sydney, reaching the quarter finals of the women's doubles with Nicole van Hooren.

In the quarterfinals, Jonathans and Audina lost to Lee Kyung-won and Ra Kyung-min of South Korea 5–15, 2–15.

She captured the women's doubles title with Mia Audina at the 2004 European Badminton Championships in Geneva, Switzerland.

She also won two silver medals (2004 and 2006) and a bronze (2002) with the Dutch squad at the European Mixed Team Championships.

Jonathans also won a bronze (2002) and a silver medal (2006) with the Dutch women's team at the Uber Cup.