He played college football for the Penn State Nittany Lions and was selected by the Buccaneers in the fourth round of the 2006 NFL draft.
[citation needed] At Penn State University, Zemaitis, a tri-captain, was a three-time All-Big Ten cornerback and was second-team All-American in 2005.
His three interceptions in the season finale at Michigan State helped seal a 31–22 victory that gave the Nittany Lions the title.
Despite a violent car accident in January 2003 that left him with several head wounds, Zemaitis played in every Penn State game over his four years and started 34 of his last 35.
He finished his career with 181 tackles, and broke the Big Ten and Penn State single-season records with 207 interception return yards in 2003.