Robert Lewandowski is firmly focused on adding to his impressive goal-haul when Bayern Munich hunt a place in the German Cup final in Tuesday's semi-final at home to Werder Bremen.

Having drawn Atletico Madrid in the last four of the Champions League, Bayern are chasing a repeat of their 2013 treble when they added the Bundesliga and cup titles to their European crown.

They host Bremen, who are fighting for survival in Germany's top flight, at the Allianz Arena for a place in the May 21 final at Berlin's Olympic Stadium.

"Now comes the important phase of the season," said Bayern hot-shot Lewandowski, the Bundesliga's top-scorer with 27 goals this season -- 38 in all competitions.

"We simply have to win after we bowed out against Borussia Dortmund at the same stage. We want to go to Berlin."

Bayern, who have won the German Cup a record 17 times, lost at home to Dortmund on penalties in last season's semi-finals.

Borussia are away to Hertha Berlin in the other semi-final on Wednesday.

On Saturday, Lewandowski scored twice within 12 minutes in Bayern's 3-0 league win over Schalke 04 having previously gone 390 minutes, and four games, without scoring.

Now the Poland hot-shot has turned his sights on Bremen, who are third from bottom in the Bundesliga.

"I'm really pleased," he said after refinding his scoring touch.

"I hope I will shoot a few more goals in the coming weeks."

Unusually for him, Lewandowski was on the bench for Bayern's 2-2 draw at Benfica last Wednesday which confirmed their 3-2 aggregate quarter-final win in Europe.

"You can't give hundred percent in every game when you play a game every three days," he said.

"Sometimes it's good to stop and then really go for it when you play again."

Dortmund are at Berlin 24 hours later in their semi-final looking to exorcise the bitter disappointment of their of last-gasp 4-3 Europa League defeat at Liverpool.

Having bowed out of Europe at the last eight stage, Borussia want to reach this year's German Cup final having lost 3-1 to Wolfsburg in the 2015 edition.

Like Lewandowski, Dortmund coach Thomas Tuchel said the goal is now to make sure his side beat Hertha to return to Berlin's Olympic Stadium for the final.

The Borussia boss rested his stars Pierre-Emerick Aubameyang and Marco Reus in Sunday's 3-0 league win over Hamburg.

He started 17-year-old Felix Passlack at left-back and goal-scorer Christian Pulisic, already a US international who only turns 18 in September on the left wing.

"We had a few changes and initially found it hard work," said Tuchel as Colombia striker Adrian Ramos netted twice.

"We're happy with the 3-0 win and now we're looking forward to the German Cup semi-final. The task is clear: we want to reach the final."

Hertha crashed to a 2-1 league defeat at Hoffenheim on Saturday, hardly the ideal preparation as they attempt to reach the German Cup final for the first time since 1993.

Hertha coach Pal Dardai lives within a stone's throw of the Olympic Stadium and is desperate to lead his team out for the cup final having always attended as a fan.

"The defeat was a wake-up call for us," said Dardai.

"We conceded two goals from dead-ball situations and we have to be very careful that the same thing doesn't happen against Dortmund at home."