Macklin, 24, spent two seasons in the Athletics organization after Oakland drafted him in the 12th round in 2011 out of North Carolina A&T University. The outfielder left for the professional ranks after his junior season in college. While in college at N.C. A&T, Macklin was a career .357 hitter in three seasons, blasting 49 home runs, including 22 during his final season in 2011. He also drove in 183 career runs. Macklin set school records in home runs, RBI and slugging percentage and was named to the Mid-Eastern Athletic Conference (MEAC) first-team all three seasons.
Macklin, a 6-1 195-pound outfielder, spent both 2011 and 2013 at Low-A Vermont in the Oakland organization. The right-handed batter and thrower compiled a .210 batting average in two seasons, covering 62 games. He had to sit out 2012 because of an injury.
Macklin spent the 2014 season with the Gateway Grizzlies, appearing in 58 games, smacking seven home runs and driving in 24 runners.