Beck was an excellent closer not because of a blazing fastball or any amazing specialty pitch, but because of his toughness and willingness to take the ball every day. Beck began his career with the San Francisco Giants, becoming an important part of the team's bullpen. Like many closers, he was a unique person, well known for his mullet, and his Fu Manchu moustache. Beck had his best year in 1993, saving 48 games while having a sparkling 2.16 ERA.

After the 1997 season, the Giants felt Beck's best years were behind him, and allowed him to leave as a free agent to sign with the Chicago Cubs, replacing him with Robb Nen. Beck set a career high in saves in his first season with the Cubs, converting 51 of 58 chances. However, in the 1999 season, Beck struggled mightily, and was dealt by Chicago to the Boston Red Sox in exchange for reliever Mark Guthrie and a player to be named later.

Beck pitched well for the Red Sox, although he struggled in the postseason and wasn't as good as he had been in the past in his two full seasons with the team. After the 2001 season, Beck had Tommy John surgery, and floated around in the minors, being signed by the Cubs organization, then traded to San Diego.

In 2003, Beck returned to the Major Leagues with the Padres, filling in for the injured Trevor Hoffman. Rod Beck pitched extremely well that year, coverting 20 saves in 20 chances, while posting an excellent 1.78 ERA. In 2004, Beck dealt with personal problems during Spring Training, and struggled in a seventh inning role for the Padres. Beck was released by San Diego in August, and is again out of baseball.