Redbridge Jewish Care B set up a semi-final showdown against Scrabble Masters after beating Los Blancos on penalties in the MGBSFL/MMFL Invitational Trophy.
The tie finished 2-2 after full-time, before RJC ran out 3-1 winners in the shoot-out.
RJC dominated possession and forged ahead when a delicious through ball from Brad Gayer was superbly finished by Craig Sandford.
The east Londoners doubled the lead when a dangerous free-kick from Gayer was dummied by Dan Andrews in the penalty area and rolled into the net.
RJC B had numerous chances to secure the match, but three top-class saves from the goalkeeper kept Blancos in contention.
Blancos started their comeback with 13 minutes to go from the penalty spot following a lapse of concentration from RJC B defence.
The whites equalised on 85 minutes with a far-post header from a set-piece, but it was RJC who held their nerve to progress to the last four.
RJC will host Scrabble Masters at the Hive on May 24, while SPEC FC are scheduled to entertain North London Raiders B two days earlier.