On June 24, 2014, Holdzkom was acquired by the Pittsburgh Pirates organization and assigned to the Double-A Altoona Curve. After posting 6.0 scoreless innings in Altoona, Holdzkom was promoted to the Triple-A Indianapolis Indians, where he recorded a 2.49 ERA in 18 appearances. Holdzkom was called up to the majors for the first time on September 2, 2014, and debuted against the St. Louis Cardinals in the 8th inning, striking out the side. Holdzkom made nine relief appearances for the Pirates in 2014, striking out 14 batters in nine innings pitched, sporting a 2.00 ERA on the year. He also pitched in the 2014 National League Wild Card Game against the San Francisco Giants.