AACHEN, April 7 (Bundesliga) - Borussia Dortmund pulled themselves out of the Bundesliga drop zone as three goals in eight second-half minutes gave them a fine win over fellow strugglers Alemannia Aachen.
Christian Worns opened the scoring for the visitors in the 14th minute but it was the two goals from Alexander Frei, and another from Paulo Cesar Tinga, in the 54th, 58th and 61st minute, that decided the game.
Vedad Ibisevic got one back for Aachen in the 63rd minute, but it proved no more than a consolation goal.
The afternoon got off to an inauspicious start for Aachen as goalkeeper Stephan Straub was injured in a collision with his own defender Thomas Stehle after just 10 minutes.
His replacement Kristian Nicht was on the pitch for only three minutes before he was picking the ball out of the net as Worns got up to head home Philipp Degen's free-kick - the ball just sneaking in off the left-hand post.
The rest of the half was largely uninspiring fare as the tension of the clash got the better of the players, but just before the interval Aachen thought they had scored through Sascha Rosler's header, only to be denied by an offside flag.
It was nine minutes after the restart that the fireworks began.
Ebi Smolarek set up his strike partner Frei who finished from 12 yards.
Four minutes later, Frei grabbed his second, latching on to a long ball from Worns to fire beyond Nicht.
With Aachen still reeling, Tinga got the fourth with a tidy close-range finish from Smolarek's cross.
Ibisevic's reply was almost immediate as the Bosnian made space for himself in the area before shooting beyond Roman Weidenfeller.
There might have been a chance for a proper comeback if the officials had spotted Dede clearing Christian Fiel's header with his hand in the 78th minute, but there was no penalty and Dortmund got away with it, much to the anger of Aachen.