Craig Breslow, a left-handed pitcher, made his presence felt in Major League Baseball (MLB) with a career that spanned over a decade. Born on August 8, 1980, in New Haven, Connecticut, Breslow attended Yale University, where he majored in molecular biophysics and biochemistry. His academic prowess earned him the nickname "the smartest man in baseball," a moniker that followed him throughout his career.

Breslow's journey in professional baseball began when he was drafted by the Milwaukee Brewers in the 26th round of the 2002 MLB Draft. However, his path to the majors was not straightforward. After being released by the Brewers in 2004, he signed with the San Diego Padres, making his MLB debut on July 23, 2005. His time with the Padres was brief, and he was released later that year.

In 2006, Breslow signed with the Boston Red Sox, where he pitched in 13 games. His tenure with the Red Sox was short-lived, and he was claimed off waivers by the Cleveland Indians in 2007. Breslow's career took a positive turn when he joined the Minnesota Twins later that year. With the Twins, he began to establish himself as a reliable relief pitcher, appearing in 42 games in 2008 with a 1.63 ERA.

Breslow's career continued to gain momentum when he was claimed off waivers by the Oakland Athletics in 2009. During his time with the Athletics, he became a key component of their bullpen, appearing in 77 games in 2009 and 75 games in 2010. His performance with the Athletics solidified his reputation as a dependable left-handed reliever.

In 2011, Breslow was traded to the Arizona Diamondbacks, where he continued to perform well out of the bullpen. However, his stay in Arizona was short, as he was traded back to the Red Sox in 2012. This second stint with Boston proved to be a highlight of his career. Breslow played a crucial role in the Red Sox's bullpen during their 2013 World Series championship run. He appeared in 61 regular-season games with a 1.81 ERA and was instrumental in the postseason, helping the Red Sox secure their third title in a decade.

Breslow remained with the Red Sox through the 2015 season, after which he signed with the Miami Marlins in 2016. His time with the Marlins was brief, and he was released mid-season. Breslow then signed with the Texas Rangers but did not make an appearance for the team.

In 2017, Breslow signed a minor league contract with the Minnesota Twins, marking his return to the team where he had previously found success. He made the Twins' Opening Day roster and appeared in 30 games that season. However, his performance was not as strong as in previous years, and he was released in July 2017.

Throughout his career, Craig Breslow was known for his intelligence on and off the field, his ability to get left-handed hitters out, and his role as a dependable bullpen arm.