Boston Town were beaten 1-0 at home by Rothwell Corinthians on Saturday.
Rob Foster’s 25th-minute goal setled the contest at the DWB Stadium.
The Poachers’ hopes of a fightback were dampened when Lori Borbely saw red for a second bookable offence in the second half.
The result sees Mark Angel’s side remain in 17th in the UCL Premier.
They will now host Desborough on Saturday (KO 3pm).