Grossman's professional debut in North America came on October 8, 2005, with Iowa. It was then that Grossman was converted to a regular defenceman, a move that led to Grossman being named Iowa's Most Improved Player after his rookie season. Grossman is one of the few Jewish players in the NHL.
Grossman scored his first career NHL goal in a Western Conference Finals game against The Detroit Red Wings on a power play. In May 2008, Grossman was given a new 2 year approx. $2M deal to stay with the Dallas Stars.