C.J. Gillman enters his second season with the ThunderBolts in 2013. He originally joined the team on June 27, 2012 and played 59 games and five different positions for that year's ThunderBolts. Gillman spent 2013's spring training with the Colorado Rockies before returning to the Frontier League. Prior to Windy City, he played at the University of Dayton, where he hit .342 over two season, including .378 in his junior year. He spent two seasons at Garden City Community College in Kansas after briefly attending Coastal Carolina and New Mexico. Prior to his collegiate career, he attended Columbine High School in Colorado.