By Oliver Trust

BERLIN, March 29 (Xinhua) -- 2013 treble winner Bayern Munich is facing significant changes on multiple levels at the club.

In advance of the Bundesliga duel against Borussia Dortmund this Saturday evening, the Bavarians are not only looking for a new coach, but according to several media reports, are searching for a replacement for their spearheading striker Robert Lewandowski.

The 29-year-old Pole is expected to set sail for Spanish giants Real Madrid. After constant rumors in German media, now the Spanish sports newspaper "AS" is reporting about Lewandowski's likely move to join the 2017 Champions League winners.

The magazine reports that Lewandowski has already informed Bayern officials such as head of board Karl-Heinz Rummenigge and president Uli Hoeness about his plans.

While Rummenigge announced Lewandowski was not for sale, the club is reportedly looking for a replacement, with Timo Werner (RB Leipzig), Edison Cavani (Paris St Germain) and Alvaro Morata (Chelsea FC) mentioned as possible successors.

Losing Lewandowski is not causing panic in Munich, despite the Pole's goal record. The new coach is expected to decide about the new striker and the team's overall tactical approach. Werner, for instance, would match a fast-forwarding style.

Lewandowski and Real will have to be patient regarding a final solution as Bayern has to solve its coaching issue first.

Possible successors of 72-year-old Jupp Heynckes, such as Nico Kovac (Eintracht Frankfurt), Ralph Hasenhuettl (RB Leipzig), Christian Streich (SC Freiburg) are mentioned in media reports.

Tottenham coach Mauricio Pochettino seems to have other plans despite loose, informal contacts with Bayern. According to the German football magazine Kicker, the Italian is considering Real Madrid.

Although Juergen Klopp's agent Marc Kosicke excluded a possible move of the current Liverpool coach to Munich, surprises seem to be not entirely ruled out.

While Bayern's leaders were under fire after former Dortmund coach Thomas Tuchel refused to join the Bavarians for the next season, new facts have since come to light.

The Berlin-based tabloid Bild reports that it was not the hesitant leaders Hoeness and Rummenigge that kept Bayern from finalizing negotiations with Tuchel, but the team's internal reservations.

According to Bild and several other media outlets, the club's stars are opposed to Tuchel as their new coach. Hummels worked with Tuchel in Dortmund and is said to be critical about Tuchel's abilities.

Rumors are speaking of the German international leaving in the case that Tuchel joins Bayern, but only time will tell if these pan out.