Darmstadt lived up to their reputation as one of the Bundesliga's best sides away from home as they frustrated 10-man Mainz to clinch another precious point in their battle to beat the drop with a goalless stalemate.
Dirk Schuster's men are behind only Bayern Munich and Borussia Dortmund in terms of results away from home and they showed how difficult they are to break down with a solid defensive display.
Pablo De Blasis missed Mainz' best chances, while Sandro Wagner had a rare sight of goal for Darmstadt, who were lent a hand by Mainz defender Giulio Donati when he earned a red card in the second half.
The draw dents Mainz's hopes of qualifying for the Champions League next season, although they remain three-points clear of Wolfsburg in the race for Europa League football.
Darmstadt pulled a further point ahead of the bottom three, with two points now separating them from the relegation play-off berth.