Aytac Sulu's first-half goal was enough to give Darmstadt the bragging rights over Eintracht Frankfurt as they claimed a 1-0 Bundesliga win in the first Hessen Derby meeting since 1982.
The centre-half headed home from Tobias Kempe's free-kick after 30 minutes to put the visitors on their way to a first win in six league fixtures and a fourth victory of the Bundesliga campaign.
Despite a lengthy amount of stoppage time - added on due to the home support burning several Darmstadt flags at one end of the ground - Frankfurt, who have won just one of their last 11 Bundesliga matches, could not salvage a point from what is just the fifth competitive meeting between the two sides.
Earlier, Werder Bremen came from a goal behind to claim a 1-1 draw at Stuttgart to climb out of the relegation play-off position.
Lukas Rupp's strike shortly after the half-hour mark put Jurgen Kramny's side in front in his first home game as Stuttgart's interim manager, but Anthony Ujah's seventh goal of the campaign earned Bremen a share of the spoils 19 minutes from time.
