A supplemental first-round pick by the Astros in 2014, the outfielder made his big league debut with Houston on June 14, 2017. In his rookie season, Fisher hit .212 with five home runs and three stolen bases as a part-time player. Fisher scored the winning run in Game 5 of the 2017 World Series, dashing home from second base on Alex Bregman's walk-off single.

A University of Virginia product, Fisher was a reserve until he was dealt to Toronto at the 2019 trade deadline for pitchers Aaron Sanchez and Joe Biagini. Through the 2019 season, Fisher has hit .191 with 16 homers and 10 stolen bases.