Erling Haaland is "almost obsessed with success" but comparing him with Robert Lewandowski is pointless, according to Michael Zorc.

Two of Europe's most feared strikers go head to head on Saturday when Borussia Dortmund host Bayern Munich in the Bundesliga.

Lewandowski was the top scorer in Europe's top-five leagues last season, hitting 51 goals to propel Bayern to a treble triumph, and he set a Bundesliga record by scoring 10 goals in the first five matchdays of 2020-21.

Haaland, meanwhile, has managed five goals in as many Bundesliga appearances this term from a total of 15 shots. That puts the Dortmund striker's shot conversion rate at 29.4, a little way behind Lewandowski's 34.5, but he has scored 66.7 per cent of his certified big chances this term, a better tally than Lewandowski's (58.3).

Haaland is 12 years Lewandowski's junior and Dortmund sporting director Zorc feels it is too soon to compare the two, although the 20-year-old's determination to succeed seems likely to see him reach similar standards.

"They are different types of players. They score a lot of goals, but they have a different age," Zorc told reporters ahead of the Klassiker.

"We're happy to have Erling. He's not just good for us because of goals, but also because he exudes a will to improve all the time.

"He's almost obsessed with success. The comparisons are for journalists and experts, not us."

Head coach Lucien Favre believes Haaland is important in terms of not conceding goals, not only scoring them.

Dortmund conceded 44 Bundesliga goals in Favre's first season in charge, which improved to 41 in 2019-20. They also kept 15 clean sheets last term compared to 10 this season before.

They faced fewer shots on target (106) than in 2018-19 (134), something Favre says is down to improved defending from across the team, as they attempt to set a Bundesliga record of five consecutive clean sheets.

"We were okay in the first year, we didn't concede a lot of goals in the first half of the season, but now we're doing better," he said.

"What matters is that we all defend. A team has to defend together – that starts with the striker. It's the whole team that has to do it."

Bayern have won all three competitive games against Dortmund under Hansi Flick, including the DFL-Supercup in September, when they triumphed 3-2.

They effectively ended Dortmund's title hopes in May with a 1-0 win at Signal Iduna Park, courtesy of Joshua Kimmich's sublime chip, but BVB were aggrieved Haaland was not awarded a penalty when a shot struck Jerome Boateng's arm in the box.

"I think the attraction is always very great. We saw the last two games were close, with only one goal settling both," said Zorc.

"We lost the last home game because of a blatantly bad decision. That's beyond dispute. We have self-confidence and we want to throw everything into the mix tomorrow to win."