The 20-year-old joined Chelsea from PSV Eindhoven in 2007, but has made just eight appearances for the side.
The Holland Under-21 international spent the second half of the season on loan at Leicester.
The 20-year-old joined Chelsea from PSV Eindhoven in 2007, but has made just eight appearances for the side.
The Holland Under-21 international spent the second half of the season on loan at Leicester.
