Zberg became a professional bicycle racer in 1996. After one season each with the Italian teams
Carrera and
Mercatone Uno–Scanavino and the
Post Swiss Team, Zberg joined the
Rabobank team in 1999. He took second place at the
Road World Championships in
Verona in 1999. A year later, he won the title at the Swiss Road Championships. He also won two stages of the 1998
Tour of Spain as well as the one-day races
Milan-Turin 1998 and
Rund um den Henninger-Turm 2001, stages of the Tour de Suisse, at Tirreno-Adriatico and the Tour of Austria. ==Major results==