Career
Castro signed with the Atlanta Braves in 2009 as a free agent. They allowed him to play for the Saraperos de Saltillo of the Mexican League to gain experience in 2012 and 2013. In August 2013, the Braves assigned Castro to the Lynchburg Hillcats of the Class A-Advanced Carolina League.
After Castro began the 2015 season with the Gwinnett Braves of the Class American Automobile Association International League, the Braves promoted him to the major leagues for the first time on June 17, 2015.
He recorded his first Major league hit against the Boston Red Sox while pinch-hitting for relief pitcher Nick Masset. He was optioned to Gwinnett the next day.
The Braves recalled Castro on July 25, after the Braves traded Juan Uribe and Kelly Johnson. Castro was optioned back to Gwinnett on August 8, along with Todd Cunningham, after the Braves acquired Nick Swisher and Michael Bourn from the Cleveland Indians.