Fresh from their 3-0 away win on March 20, United were 2-0 victors at the Jakemans Community Stadium.
Ezra Aaron and Luke Horne scored the Pilgrims’ first half goals in a routine home victory.
Boston: Daniel Martin, Rueben Fogg, Josh Doran, Will Langford, Ellis Perry-Burdett (Dexter Tomlinson 75), Taylor Jaine, Jake Henderson (JJ Ward 46), Kris Zaluzinskis, Ezra Aaron (Nathan Bowen 70), Lucas Turrell (Joe Wilkinson 70), Luke Horne.
Referee: Peter Brothwell.