St Paul's suffered their first Le Riche Cup defeat since March 2009 as they were beaten 1-0 in the semi-finals by 10-man Jersey Scottish.
Charlie Petulla scored the only goal with a long-range free-kick that eluded everyone and found the corner.
Barry Keith was then sent off for stamping on St Paul's captain Luke Watson mid-way through the second half.
But Jack Cannon missed a penalty for St Paul's after Craig Fletcher brought down Craig Russell in the box.
St Paul's, who dominated the game for long periods, had been seeking to win the Cup for a fourth consecutive year.
Scottish, who are top of the Jersey Premiership, will now face Jersey Wanderers in the final next month.