Forfar stunned their more illustrious opponents Dunfermline in the first round of the Ramsdens Cup.
The Second Division side opened the scoring on 13 minutes when Omar Kader converted Danny Denholm's cross.
Dunfermline, relegated from the Scottish Premier League to the First Division last season, levelled when Ryan Wallace fired home from 12 yards.
The Pars were in front before half time, Andrew Barrowman finding the net with a low shot.
Denholm's drive levelled the match eight minutes after the break and Gavin Swankie pounced from close range to seal victory.
Forfar: Soutar, McCulloch, Dunlop, Iain Campbell, Bolochoweckyj, King (Motion 72), Kader (Ross Campbell 80), Keith Gibson, Denholm, Templeman (Fotheringham 72), Swankie. Subs Not Used: Scott, Tulloch.
Booked: Motion, Ross Campbell.
Goals: Kader 13, Denholm 53, Swankie 66.
Dunfermline: Gallacher, Geggan, Potter, Dowie, McMillan, Husband (Kane 67), Thomson (Whittle 77), Falkingham, Cardle, Barrowman, Wallace (Kirk 67). Subs Not Used: Goodfellow, Burns.
Booked: Husband, Dowie.
Goals: Wallace 16, Barrowman 35.
Ref: Kevin Clancy