The 19-year-old, who impressed following his switch from Brigg Town in January, was offered new terms for the 2012-2013 season and has officially signed the paperwork.
The former Grimsby Town player made 16 appearances for the Pilgrims after his mid-season arrival at The Jakemans Stadium.
Marshall’s signature is the first of what manager Jason Lee hopes to be a number of players signing new deals.
Stay tuned to bufc.co.uk for news as soon as it is available…