Barnes attended Katella High School in Anaheim, California, where he excelled in baseball and football.

A talented free safety in football, Barnes did not even play baseball during his senior year at Katella High, and signed a letter of intent to play football at UCLA, but withdrew after a coaching change.

Despite Cypress being NJCAA, several MLB players have competed for the school's program, including Trevor Hoffman, Ben Francisco, Jason Vargas, and Gerald Laird.

He hit a ground rule double to deep right field, scoring Ronny Cedeno, as the Astros beat the Colorado Rockies 3 to 2.

[5] On December 3, 2013, Barnes was traded to the Colorado Rockies with pitcher Jordan Lyles for outfielder Dexter Fowler and a player to be named later.

[6] On June 14, 2014, he struck a two-out, two-run inside the park home run off the San Francisco Giants Sergio Romo to lead the Rockies to a 5-4 victory.

[8] In 109 games for the Triple–A New Orleans Baby Cakes, he batted .276/.331/.420 with 11 home runs, 49 RBI, and 15 stolen bases.