Career
In the 2000-2001 season, Bollmann was transferred from SpVgg Beckum to South Carolina Paderborn 07. With his club, he was promoted to the 2. Bundesliga. Later in the summer of 2006, he joined Arminia Bielefeld.
After a period of settling in, he was regularly capped in the second half of the 2006-2007 season, with the result that in May 2009 his contract was prolonged to 2012.