kirschke signed with the pittsburgh steelers as an unrestricted free agent on march 11, 2004. in his first season with the team he played in all 16 games and finished the season with 12 tackles and one sack. in 2005, he was part of the steelers team who won super bowl xl and finished the year 13 tackles and one sack. the following year, he made eight tackles and equaled his career-high total of two sacks. in 2007, he finished the campaign with 26 tackles and two sacks.