 He played in twelve games during his rookie season, recording two sacks and 26 total tackles.He was declared inactive for the first four weeks of the 2002 NFL season, before being suspended for the next four games by the NFL for a repeated violation of the league's substance abuse policy.Robertson's suspension ended on October 28, 2002, and he was subsequently placed on the team's reserve/non-football illness list, where he spent six weeks.