A 1-1 draw was enough for Schalke to see off Levski Sofia and reach the Uefa Cup semi-finals as they secured a 4-2 aggregate victory.
The Bundesliga side did the hard work when they secured a 3-1 win in Bulgaria in the first leg, but had to ward off trouble after Emil Angelov scored in the first half.
However Brazilian midfielder Lincoln levelled matters just before the hour mark and Schalke closed out the game to set up a high-profile meeting with Sevilla in the last four.
Levski begun the encounter knowing they needed to score at least three times to spring an upset at the Arena AufSchalke, and after 24 minutes the German favourites were left with a few nagging doubts when Angelov made his intervention.
The Levski star fired home with a low drive after picking up the ball from Valeri Domovchiyski to send the visiting fans into raptures.
Schalke looked to restore their comfort zone but German international Kevin Kuranyi and Danish striker Soren Larsen both wasted good chances.
However on 58 minutes Lincoln ensured their progression as he reacted quickly to steer home a loose chance in the penalty area after Kuranyi had helped the ball on its way from a throw-in.
A fantastic first leg provided the basis for the two-legged victory, and Schalke will be sure to face a sterner test in the last four in the form of Primera Liga side Sevilla.
Click below for match summary:
Schalke 1-1 Levski Sofia (4-2 on aggregate)