Leon Squire had put the Pilgrims in front against Chesterfield at RAF College Cranwell — but two spectacular free-kicks won it for the visitors.
It was a much-changed line-up for United — with Steve Welsh’s eyes firmly fixed on Wednesday’s FA Youth Cup tie against Pegasus Juniors at The Jakemans Stadium.
Boston (4-3-3): Tom Benton; Harry Bunce, Josh Spencer, Ollie Price (Billy Hodgkiss 46), Corey Newman; Miles Lynch (Bradley Easey 46), Jacob Pease, Joe Searson; Will Quigley (Leon Squire 46), Liam Moran (Karolis Andriulionis 46), Steven Dovey (Juris Kormis 46).