From 1907 through 1917, he played for the St. Louis Cardinals (1907–1909), Pittsburgh Pirates (1909–1913), Philadelphia Phillies (1913–1917) and Chicago White Sox (1917).

Acquired by the Pittsburgh Pirates in late August 1909, Byrne made an immediate impact contributing down the stretch, and allowing Tommy Leach to remain in the center field.

Despite a low .259 batting average in 1911, Byrne scored 96 runs with 23 stolen bases and set career highs in triples (17) and games played (153).

In the 1913 midseason, Byrne was traded by Pittsburgh pirates, along with pitcher Howie Camnitz to the Philadelphia Phillies in exchange for utility player Cozy Dolan and cash considerations.

In 1917, he was selected off waivers by the Chicago White Sox from the Phillies, making his final major league appearance in the 1917 World Series.