Hamlett spent his entire professional career in the US, playing with the Fort Lauderdale Strikers and the Colorado Rapids, as well as indoor soccer with the Harrisburg Heat and Anaheim Splash.

After his parents separated, Hamlett moved to the United States to live with his mother in Silver Spring, Maryland when he was ten years old, where he attended Albert Einstein High School.

[1] In 1987 Hamlett began playing college soccer for UNC Wilmington, before transferring to George Mason University in Fairfax, Virginia after his freshman season.

Denis took up the post of interim coach of the men's soccer team at the Illinois Institute of Technology for the 2010 season, leading them to a conference title and playoff final appearance.

On November 14, 2023, the Red Bulls fired Hamlett from the sporting director position along with not renewing head coach Troy Lesesne's contract.

[14] Hamlett was appointed first-ever sporting director MLS Next Pro club Connecticut United in January 2025.