Carmarthen Town hit three goals in the last half hour to book their place in the FAW Premier Cup quarter-finals. Nathan Cotterall broke the deadlock on the hour when he was fouled in the box and converted from the penalty spot.
Kaid Mohamed doubled the lead 13 minutes later but Ashley Stott replied for Bangor 10 minutes from time and then had a shot cleared off the line.
But Carmarthen sealed the win when Cotterall broke away as Bangor pushed forward to scored Carmarthen's third.
Carmarthen: Neil Thomas, Terry Evans, Paul Keddle, Liam Hancock, Mark Dodds, Chris Thomas, Danny Thomas (Hayden Fleming 80), Tom Ramasut (Aswhley Williams 90), Paul Fowler, Kaid Mohamed (Mattie Davies 80), Nathan Cotterall.
Subs Not Used: Sasha Walters, Craig Lima.
Booked: Tom Ramasut, Mattie Davies.
Goals: Nathan Cotterall (pen) 60, Kaid Mohamed 73, Nathan Cotterall 90.
Bangor City: Ian Havard, Kyle Jacobs, Kevin Scott, Melvin McGinness, Lee Webber, Martin Beattie, Marc Lloyd Williams, Ashley Stott, Sion Edwards, Carl Jones (Paul Roberts 60), Michael Walsh.
Subs Not Used: Adam Docker, James Marsden, Jon Newell, Alan Karim.
Booked: Carl Jones, Melvin McGinness, Ian Havard, Ashley Stott, Sion Edwards.
Goals: Ashley Stott 80.
Referee: Mark Whitby (Penallergeor).