Justin Duchscherer, a right-handed pitcher, began his Major League Baseball career with the Texas Rangers. Drafted by the Boston Red Sox in the eighth round of the 1996 MLB Draft, he spent several years in the minor leagues before being traded to the Rangers in 2001. Duchscherer made his MLB debut with Texas on July 25, 2001, but his time with the team was brief, appearing in only three games that season.

In 2002, Duchscherer was traded to the Oakland Athletics, where he would spend the majority of his career. Initially, he continued to develop his skills in the minor leagues, but by 2003, he had earned a spot on the Athletics' roster. Duchscherer found his niche as a relief pitcher, becoming a reliable option out of the bullpen. His performance in 2004 was particularly impressive, as he posted a 2.21 ERA over 53 appearances, earning him a place in the All-Star Game as a replacement for an injured player.

Duchscherer's success as a reliever continued through the 2005 and 2006 seasons. In 2005, he maintained a 2.91 ERA over 65 games, and in 2006, he recorded a 2.91 ERA once again, this time over 53 games. His ability to consistently deliver strong performances made him a valuable asset to the Athletics' pitching staff.

In 2008, Duchscherer transitioned from the bullpen to the starting rotation, a move that proved to be beneficial for both him and the team. That year, he achieved a career-best 2.54 ERA over 22 starts, earning his second All-Star selection. His performance placed him among the league leaders in ERA, showcasing his adaptability and skill as a pitcher.

However, Duchscherer's career was not without its challenges. Injuries began to take a toll, limiting his playing time in subsequent seasons. In 2009, he missed the entire season due to elbow surgery and a battle with clinical depression. Despite these setbacks, Duchscherer made a comeback attempt in 2010, returning to the Athletics' rotation. Unfortunately, his season was cut short due to a hip injury, and he appeared in only five games.

After his time with the Athletics, Duchscherer signed with the Baltimore Orioles in 2011, hoping to revive his career. However, persistent injuries prevented him from making a significant impact, and he did not appear in any games for the Orioles.

Throughout his career, Duchscherer demonstrated the ability to excel both as a reliever and a starter.