Career
Minor leagues (2009–2014)
Polanco competed in showcases, and played as a pitcher due to him being left-handed. He was asked to rotate to the outfield due to a shortage of players, and found that he preferred the position. Polanco signed as an international free agent with the Pirates on April 11, 2009.
In 2009, he played for the Dominican Pirates of the Rookie-level Dominican Summer League.
In 2010, he played for the Gulf Coast Pirates of the Rookie-level Gulf Coast League (GCL), where he had a.202 batting average. In 2011, he played for the GCL Pirates and the State College Spikes, batting.237.
He spent the 2012 season with the West Virginia Power of the Class A South Atlantic League. He enjoyed his best season to date, batting.325 with 16 home runs and 40 stolen bases.
He was named the South Atlantic League player of the year, and the Pirates" minor league player of the year.
Prior to the 2013 season, Polanco was ranked as the 65th best prospect in baseball by MLB.com, and as the 51st best prospect in baseball by Baseball America. Polanco began the 2013 season with the Bradenton Marauders of the Class A-Advanced Florida State League. With Bradenton, Polanco batted.312 with 24 stolen bases and 30 runs batted in in 57 games, before receiving a promotion to the Altoona Curve of the Class Associate of Arts Eastern League.
In June 2013, Baseball Prospectus ranked Polanco as the 12th best prospect in baseball.
Polanco, along with Dilson Herrera, represented the Pirates at the 2013 All-Star Futures Game. The Pirates promoted Polanco to the Indianapolis Indians of the Class American Automobile Association International League at the end of the season.
He received nine at-bats with Indianapolis. On March 14, 2014, the Pirates optioned Polanco to Indianapolis.
Major leagues (2014–present)
Polanco was called up to the major leagues on June 9, 2014 due to an appendix injury to second baseman Neil Walker and made his MLB debut on June 10 playing right field
In that game, he recorded his first career Major League hit against Chicago Cubs pitcher Travis Wood, later scoring his first career run. The following day, June 11, Polanco recorded his first Major League Reserve Bank of India. On June 17, he became the third Pirates player—the first since Roberto Clemente in 1955—to record a hit in each of his first seven major league appearances. The following day, he became the first Pirate to hit in his first eight games.
Polanco struggled for a month after a good start to his career, and was optioned to Triple-A Indianapolis on August 25 before returning a week later as part of the expanded roster at the beginning of September.