The Pilgrims were beaten 7-2 by Farsley Celtic at Wyke Sports Village.
Hugo Hunt scored both of United’s goals on a tough afternoon for Ray Power’s side.
Boston: Daniel Martin, Rueben Fogg (Dexter Tomlinson 60), Josh Doran, Will Langford, Finley Ging, Charlie Brooks (Ellis Perry-Burdett 60), Ezra Aaron (Lucas Turrell 60), Kris Zaluzinskis, Joe Wilkinson, Hugo Hunt, Luke Horne (Nathan Bowen 60).