Ousmane Dembele inspired a sensational comeback as Borussia Dortmund beat Bayern Munich in the Allianz Arena to progress to a record fourth consecutive German Cup Final.

Despite taking a first-half lead through Marco Reus, Dortmund looked like suffering a repeat of their recent heavy league defeat as goals from Javi Martinez and Mats Hummels gave a dominant Bayern a 2-1 halftime lead. But after Sven Bender's defensive heroics after the break, 19-year-old Dembele first set up Pierre-Emerick Aubameyang to equalize before firing home a stunning winner.

Aubameyang had returned to the starting line-up after starting on the bench against Borussia Mönchengladbach and Julian Weigl replaced the injured Nuri Sahin in midfield. Lukasz Piszczek also returned at the back as Dortmund lined up in a 4-3-3 formation.

Jerome Boateng aside, Carlo Ancelotti had a full squad at his disposal and, perhaps in acknowledgement of the importance of this competition following Bayern's Champions League exit, started with his strongest possible XI, Arjen Robben, Franck Ribery and Robert Lewandowski leading the line.

Dortmund coach Thomas Tuchel had said his team were "ready to deliver a big performance" in the Allianz Arena and they could have been ahead inside five minutes but Aubameyang couldn't connect with Raphael Guerreiro's cross in the six-yard-box.

Just as Bayern were easing their way into the game, Dortmund did take the lead. Guerreiro pounced on a lose backpass from Martinez but his shot hit the post, but Marco Reus was on hand to tap home the rebound.

Bayern dominate

The lead lasted barely ten minutes as Martinez, making up for his earlier error, drew Bayern level with a powerful header. He almost repeated the same trick shortly after, but this time the Spaniard's header came back off the upright, as Bayern took control.

As half-time approached, the hosts got their reward for their increasing dominance when center-back Hummels, left unmarked in the box after advancing for a corner, tucked away Ribery's pass with all the finesse of a top striker. Indeed, Dortmund were fortunate to go into the break only one goal behind after Roman Bürki saved one-on-one with Lewandowski in first half injury time.

Tuchel replaced Gonzalo Castro with Erik Durm in the second half but, for the next fifteen minutes, it only seemed to have the effect of emphasizing Bayern's dominance. While those in yellow chased and worked, their red-shirted tormenters seemed to toy with them at will.

Dortmund heroics

Just after the hour-mark, the otherwise solid Bürki inexplicably played a short pass into the path of Thiago Alcantara who squared to Lewandowski in the area but the Pole, with the goal at his mercy, forwarded the ball onto Robben whose shot was heroically saved on the line by Bender.

Tuchel had spoken of needing a bit of luck in order to win in Munich and, despite the score, his team were getting it. Going forward however, Dortmund simply weren't posing enough of a threat. Until Dembele decided enough was enough.

First it was his sumptuous cross which found Aubameyang at the back post. It was a wonderful ball and, this time, the Bundesliga's top scorer made no mistake. Five minutes later, the provider turned scorer.

When Reus miscontrolled in the Bayern box, it looked like the chance has gone. But the German still managed to find Dembele who curled a brilliant shot into the top corner to turn the tie on its head and set up a Berlin date with Eintracht Frankfurt.