
The 18-year-old, who turns 19 in March, has been in impressive form for the Zebras since joining Brigg from Grimsby Town earlier in the campaign.
Marshall was close to being awarded a professional contract by Grimsby bosses Rob Scott and Paul Hurst in the summer, but he was released from Blundell Park at the end of August.
The young defender has established himself in senior football during almost five months with Brigg and has been registered by the Pilgrims in time to be available to make his debut against Nuneaton Town on Saturday.
Stay tuned to bufc.co.uk for full-match build-up to Saturday’s clash against Nuneaton — plus the reserves’ trip to CGB Humbertherm.