Ryan Klesko's journey in Major League Baseball began when he was drafted by the Atlanta Braves in the fifth round of the 1989 MLB Draft. Known for his powerful left-handed swing, Klesko quickly rose through the minor league ranks, making his MLB debut with the Braves in 1992. Over the next several years, he became an integral part of the Braves' lineup, contributing to the team's success during the 1990s.

Klesko's breakout season came in 1994 when he hit 17 home runs in just 94 games, showcasing his potential as a power hitter. The following year, he played a crucial role in helping the Braves secure the World Series title, hitting a home run in three consecutive games during the series against the Cleveland Indians. This achievement made him the first player in World Series history to accomplish such a feat.

Throughout his tenure with the Braves, Klesko was primarily utilized as a left fielder and first baseman. His ability to hit for power was complemented by a respectable batting average, making him a valuable asset in the Braves' lineup. In 1996, he had one of his best seasons, hitting 34 home runs and driving in 93 runs, further establishing himself as a reliable offensive player.

In 1999, Klesko was traded to the San Diego Padres, where he continued to be a productive hitter. His first season with the Padres saw him hit 26 home runs and drive in 92 runs, maintaining his reputation as a power threat. Klesko's time in San Diego also allowed him to showcase his versatility, as he played both first base and the outfield.

The 2001 season was particularly noteworthy for Klesko, as he achieved career highs in several offensive categories. He batted .286 with 30 home runs and 113 RBIs, earning him an All-Star selection. This performance solidified his status as one of the premier power hitters in the National League during that period.

Klesko's later years with the Padres were marred by injuries, which limited his playing time and production. Despite these setbacks, he remained a respected figure in the clubhouse and continued to contribute when healthy. In 2006, he underwent shoulder surgery, which sidelined him for most of the season.

In 2007, Klesko signed with the San Francisco Giants, hoping to revitalize his career. He played in 116 games, hitting .260 with 6 home runs and 44 RBIs. Although his power numbers had declined, he provided veteran leadership and experience to the Giants' roster.

After the 2007 season, Klesko announced his retirement from professional baseball. Over the course of his career, he amassed 278 home runs, 987 RBIs, and a .279 batting average. His ability to deliver in clutch situations and his consistent power-hitting made him a respected player throughout his time in the majors.