Hamm competed at the 2000 Olympics in Sydney at age 17, and the 2004 Summer Olympics in Athens, alongside his twin brother Paul. At the 2004 Olympics, he won the silver medal with the U.S. team in the team competition. Morgan's contribution to this medal-winning performance was vital as he performed on four of the six apparatus and was the highest scorer for the team on vault and high bar. He also competed in floor and high bar finals, and only a tie-breaker kept him from winning the bronze medal on the latter event. Morgan was also a member of the U.S. team at the 2003 World Championships that won a silver medal in the team competition.