Westberg initially started his football career with FC Saint-Cloud located not far from his hometown. He later had a stint at first division club Paris Saint-Germain training at the Camp des Loges before moving on to FC Issy-les-Moulineaux in southwest Paris.
Westberg began his football career with FC Saint-Cloud, which was close to his hometown. Later, he had a period at Paris Saint-Germain in the first division, training at Camp des Loges before moving to FC Issy-les-Moulineaux in southwest Paris.