He joined the Lions from Leeds United in the summer after impressing on trial following his release from Elland Road.
The 21-year-old full back has made 26 appearances for the Lions this season.
But Ferguson has now signed for Portland Timbers 2, who compete in the Pacific Division of the MLS Next Pro league.
Taylor Bowen left Guiseley and made the move to the States in October, while another young Lions ace is heading over there later this year.
Defender Freddie Westfall is still only a teenager, and with the centre back understandably not yet a first-team regular at Nethermoor, this is a chance to do things differently.
He has been snapped up by the Sports Recruting USA (SRUSA) Elite Academy, which allows young footballers, often from the UK, the chance to play college soccer in America.
Not shy of putting in a tackle, former Guiseley Academy captain Freddie Westfall would be an asset to any college side out in America. (Image: Alex Daniel)
Still only just beginning his journey in first-team football, Westfall got vital experience under his belt with Steeton in the North West Counties Football League First Division North, while there on dual registration.
Before then, he spent several years in Sheffield Wednesday’s academy.
Westfall will be available to American college sides in the autumn, while his agent will be Joe Stacey (joe@sportsrecruitingusa.com).