Brian plays for Seattle University as a catcher and designated hitter. Olson was a three year starter for the Tahoma High School Bears. He helped the team reach the state playoffs at Safeco Field his sophomore year and the preliminary rounds his junior and senior years. He was named All-State Catcher in 2011 by The Seattle Times and named First Team All-Division in 2009 and 2011. He made the division's second team in 2010. He was also given the Underclassman Award, the 2009 Batting Championship, and Gold Gloves in 2010 and 2011. He hit .485 his sophomore year, and helped the Bears win all but one league game his senior year. He also was given the All-Academic award his three years on the varsity team.