[1] Harrer began her career as ice hockey goaltender at the age of 5 at SB Rosenheim.

[2] Later she trained with TEV Miesbach and was the regular goaltender with the ESC Planegg in the Ladies-Bundesliga, before she ahead of the season 2003/04 moved to her grandparents in Reichersbeuern, to play in the DNL (Rookie)-Team of Tölzer Löwen (Lions of Bad Tölz).

Eishockey-Bundesliga she transferred to TSV Erding, where her elder brother Daniel had played for several years.

In the season 2010/11, she played for TSV Erding in the Deutsche Fraueneishockey-Liga (women league elite in Germany).

[3] Already at the age of 16 years old, she belonged to the extended squad if the Deutsche Nationalmannschaft (German Ladies Ice Hockey National Team) and traveled to the 2003 World Championship in Peking, which was canceled due to the SARS-Epidemics.