Fortuna Duesseldorf boosted their hopes of avoiding relegation from the Bundesliga after coming from behind to beat Schalke 2-1 at home on Wednesday.
The result left Fortuna 16th, the relegation playoff spot, on 27 points from 28 games, one behind Mainz who stayed in the safety zone with a 1-1 draw at Union Berlin. Schalke stayed ninth on 37 points.
The match was played behind closed doors due to the COVID-19 pandemic and the first half only produced a long-range effort at either end as both sides applied a cautious approach.
Yet their joy was short-lived as Hennings nodded in a 63rd-minute equaliser, which stood after a quick VAR check, having beaten his markers to the ball after visiting keeper Markus Schubert parried a ferocious Kevin Stoeger free kick.
More sloppy defending allowed the hosts to complete their comeback five minutes later, as Karaman headed the ball in from one metre after Erik Thommy's cross was nodded into his stride.
Schalke threw men forward in the closing stages but created almost nothing as the home team's packed defence dealt with their aimless long balls easily, while also looking dangerous on the break.
Fortuna should have netted a third in stoppage time after Schubert was left stranded having misjudged a long clearance, but substitute Steven Skrzybski saw his weak shot cleared off the line.