Hansi Flick says Bayern Munich must "become closer together as a team" in star striker Robert Lewandowski's absence, while Joshua Zirkzee could get his first-team chance.

Lewandowski has been a near ever-present in his six-year Bayern career, but the 31-year-old has been ruled out for four weeks after suffering a knee injury against Chelsea in the Champions League on Tuesday.

Bayern have a 3-0 first-leg lead in their European tie but are engaged in a tense Bundesliga title tussle, meaning the loss of a striker who has scored 39 goals in all competitions comes as a weighty blow.

Interim head coach Flick did not hide from the significance of the setback as he addressed the media ahead of Saturday's match against Hoffenheim, also discussing Kingsley Coman's status after he hobbled off at Chelsea.

"With Kingsley, we hope that he will only be out for five days. Robert's situation is different," Flick told a news conference.

"Of course, Robert has shown what quality he has, not just in front of goal. The past few games have also shown that he is someone who fits perfectly into the team.

"He is a source of inspiration for who we are defensively, too, and therefore he is so important to us.

"It is crucial that we all become closer together as a team now and successfully use the time that he is missing."

Flick would not confirm how Bayern will line up at Hoffenheim - although Philippe Coutinho will feature - but Serge Gnabry, Thomas Muller and 18-year-old Zirkzee are all in his thinking for a central striking role.

The Netherlands youth international has already scored twice in the Bundesliga but has made just three fleeting substitute appearances.

"There are a lot of considerations," Flick said on Friday. "But it is always good if the opponent puzzles over something and does not get all the information.

"Serge is of course a candidate, and Thomas could also play in this position. We leave that open.

"Joshua Zirkzee is also a player who is in the squad and will therefore be included in the considerations. We need him in the squad because we are not richly blessed in that position."