Williams was signed by the Green Bay Packers as an undrafted free agent in 2016, later playing for the Saskatchewan Roughriders of the Canadian Football League (CFL), the San Antonio Commanders of the Alliance of American Football (AAF), and the New York Guardians of the XFL.

[12] In May 2017, Williams signed as a rookie free agent with the Saskatchewan Roughriders of the Canadian Football League (CFL).

In May 2018, Williams took reps against the Edmonton Eskimos in the opening preseason game of the 2018 CFL season, completing 3 of his 7 pass attempts for 32 yards and an interception.

[14] In the inaugural AAF quarterback draft, the San Antonio Commanders used their second-round pick on Williams, who had initially been allocated to the Atlanta Legends.

[15] He was primarily used as a change-of-pace backup, earning a handful of plays but filling in well whenever starter Logan Woodside was benched or injured.

Williams completed over 70% of his passing attempts, including a touchdown and a two-point conversion, and rushed for nearly six yards per carry.

Williams' completed 23 out of 48 passes in relief work, as well as being used as a situational rusher with 5 carries for 29 yards and a touchdown.

Marquise streams himself on the football based game, Madden NFL 21, in front of his viewers.