Greg Nixon was an All-American sprinter and football standout for Howard Payne. After HPU, he  specialized in the 400 meters, becoming a three-time world champion and two-time USA champion. In his junior year in 2005-2006, Nixon started running track. With only a few months of training, he won the 200 meters at the NCAA Division III championships. As a senior, Nixon won the 100- and 200-meter national championships to become a four-time All-American. He also won conference championships in the 100 and 200 meters and was named American Southwest Conference Athlete of the Year. After college, Nixon started running the 400 meters, winning the 2007 U.S. Indoor National 400 meters after only having run it four times. Also in 2007, Nixon also made his first USA outdoor team and ran in the Pan American games, earning a silver medal in the 4x400 meter relay. Nixon won a gold medal in the 2008 World Indoor Championships 4x400 meter relay and made it to the finals in the U.S. Olympic trials, placing seventh. In 2009, he led the world in the 400 meters and 200 meters and the indoors 300 meters. In 2010 Nixon made another U.S. Indoor world team, winning a second gold medal. In the 400 and then won the U.S. Outdoor title in the 400 with a world leading time of 44.61. He was on the USA 4X400 meter relay that won the 2011 World Outdoor Championship. Nixon currently lives in New Orleans and is co-founder of Beyond 3D Studios and Ubuntu Construction Company.

His career highlights after Howard Payne include-
USA Championships
2010 USA Outdoor 400m champion (44.61) - fast time in the world at the time
2007 USA Indoor 400m champion (46.75)
International Championships
2011 World Outdoor 4x400m gold medalist (2:59.31)
Two-time World Indoor 4x400m relay gold medalist – 2008, 2010
2007 Pan Am Games 4400m relay silver medalist