Morton attended the University of Michigan where he played college football under head coach Bo Schembechler. After playing a reserve role in 1973, Morton was a starting defensive tackle for the Wolverines in 34 of 35 games from 1974 to 1976. Despite being only 6 feet, 2 inches, and 225 pounds, Morton became one of the best defensive linemen in the college game. Bo Schembechler called Morton the "quickest, most aggressive tackle in America," and added, "He's super quick, reacts like a cat and is surprisingly strong." In 1974, he started all 11 games at the defensive tackle position for the 1974 Michigan Wolverines football team that held its opponents to an average of 6.8 points per game. In 1975, Morton started 11 of 12 games at the defensive tackle position for the 1975 Michigan Wolverines football team that played in the 1976 Orange Bowl and finished the season ranked No. 8 in both the AP and UPI polls. Morton compiled 107 tackles and 11 sacks for 58 yards in 1975 and was selected as a first-team All-Big Ten player. In December 1975, the Associated Press published a feature story focusing on Morton's fondness for exotic flora, including a purple passion plant that Morton had named Claudine. The Los Angeles Times dubbed him "Michigan's Plant Man." In his final season of collegiate football, Morton started all 12 games at defensive tackle for the 1976 Michigan Wolverines football team that won the Big Ten Conference championship, held opponents to an average of 7.9 points per game, played in the 1977 Rose Bowl and finished the season ranked No. 3 in both the AP and UPI polls. For the second consecutive year, Morton was selected as a first-team All-Big Ten player by both the AP and the UPI. He was selected by the ABC television network as the 1976 defensive player of the year in college football. He received the award ceremony broadcast on ABC during the Liberty Bowl; Tony Dorsett received the award as offensive player of the year. At the end of his collegiate career, Morton had 268 career tackles. He ranked third in Michigan's record book in both career tackles and career tackles for loss. In 1977, Morton received a bachelor of arts degree in history.
Professional football
Morton was selected by the Buffalo Bills in the eighth round of the 1977 NFL Draft. He appeared in nine games for the Bills during the 1977 NFL season, but he spent much of the season on the bench. In early December 1977, the Bills placed Morton on the inactive list to make room for a third quarterback to be added to the roster.
Later years
After the 1977 season, Morton opted to return to the University of Michigan to pursue a doctoral degree from the school of education. He subsequently became a probation officer in Fort Worth, Texas. As of 2002, he was also officiating high school football games in the Fort Worth area. In 2001, Morton was inducted into the Summit County Sports Hall of Fame. In 2019, Morton auditioned for the 14th Season of Amerca's Got Talent. He gave an introduction saying that he also did impressions for action figures and was also a PA announcer for a department store. After the intro, he did a few Star Wars impressions. The audience was stunned by a few of them, including when Luke Skywalker's arm got sliced off, R2-D2 & C-3PO, Jabba the Hut, Emperor Palpatine, and finally, Chewbacca, which made the audience stand up on their feet. Judges Howie Mandel, Julianne Hough, Gabrielle Union, and Simon Cowell all voted "Yes," sending Greg to the Judge Cuts. Morton's Judge Cuts performance consisted of performing impressions of characters from various movies, like Jurassic Park, E.T., Godfather, Lord of the Rings, Back to the Future, and even Buzz Lightyear from Toy Story. Mandel, Union, Hough, Cowell, and guest judge Ellie Kemper gave him standing ovations. Morton's performance was strong enough to advance to the Quarterfinals along with Marcin Patrzalek on a unanimous verdict. His Quarterfinals performance consisted of performing more impressions of characters from various "animated" movies, including Lion King, Aladdin, Shrek, Guardians of the Galaxy Vol. 2 and even Terminator and Heath Ledger's Joker. The judges all gave him yet another standing ovation. He received enough votes to advance to the Semifinals in Episode 1412 along with Messoudi Brothers instead of Bir Khalsa. Finally, Morton's Semifinals performance voices of famous cartoon characters, including Looney Tunes, Flintstones, Shaggy & Scooby-Doo, and Bobby from "Bobby's World", which surprised Howie Mandel. The four judges and guest judge Sean Hayes gave him a final standing ovation. It was then that Morton did not receive enough votes to advance to the Finals, eliminating him from the competition instead of Kodi Lee.
