The 23-year-old striker has joined Pools on loan from Fleetwood Town until the end of the 2020-21 season.
He becomes the club’s third and final deadline day arrival following the loan signing of goalkeeper Brad James and the short-term permanent capture of left-back Zaine Francis-Angol from Boreham Wood.
Saunders grew up in the north east and represented Barnard Castle and Darlington Railway Athletic at youth level before going on to play for Bishop Auckland, Durham City and Darlington FC, where he scored 11 goals in 66 games before stepping up to the Football League with Fleetwood Town in 2019.
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The forward has scored eight times in 29 games for The Cod Army in all competitions this season.
He arrives at Pools with Stockport County loanee Richie Bennett likely to return to his parent club after netting a hat-trick for Hartlepool at Wealdstone last Saturday.