- Born: 07/16/1985 in Livingston, New Jersey
- Birthname: Michael Cuellari
- Height & Weight: 6'0", 234 Ib
- GPW Southern States Championship (2 times)
- JCW Heavyweight Championship
- IWA Puerto Rico Championship
- MFPW Heavyweight Championship
- MFPW Tag Team Championship – with Punishment Martinez
- SCW Florida Heavyweight Championship (3 times)
QT Marshall is a co-owner and trainer of The Nightmare Factory (formerly known as One Fall Power Factory), a professional wrestling training facility, alongside Cody Rhodes and Glacier of Nightmare Family. He is otherwise known for his career in All Elite Wrestling.
During his career he has worked with several independent promotions, most notably having sporadic appearances in Ring of Honor (ROH), as well as four matches with WWE. He also was the focus of a documentary about his tryout for the WWE named The Wrestler: A Q.T. Marshall Story, which has won Best Documentary at the 2017 San Diego Comic-Con Film Festival.