In this July 27, 2019 photo, Manchester City's midfielder Leroy Sane (right) runs with the ball past Yokohama F. Marinos' goalkeeper Park Iru-gyu during a friendly football match between English Premier League club Manchester City and Japan League Yokohama F. Marinos at the Yokohama Stadium, in Yokohama. (CHARLY TRIBALLEAU / AFP)

An unwritten rule of German soccer seems to have lost its relevance of late. For decades, fans, media and clubs have accepted that if Bayern Munich sets out to acquire a new signing from a domestic rival then there is nothing anyone can do to stop that player from joining the Bavarian giant.

Bayern supposedly viewed Timo Werner as a potential backup or strike partner for Polish target man Robert Lewandowski－regarded as a very similar player to Werner

The curious case of Timo Werner, however, seems to indicate that times have changed. German media report that the 24-year-old RB Leipzig striker has rejected an offer to join Bayern this summer.

As a result of Werner's shock snub, the 2013 treble winner has intensified its efforts to sign Manchester City attacker Leroy Sane.

Bayern coach Hansi Flick is reported to have had a 30-minute phone chat with Germany international Sane recently, while sports director Hasan Salihamidzic is said to be conducting negotiations with the reigning English Premier League champion.

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Werner's decision not only opens the doors for a Sane exit at City but increases the possibility of a Werner move to runaway Premier League leader Liverpool.

The Reds' German boss Jurgen Klopp is said to be keen on Werner and is going all out to convince the Germany forward that Anfield would be the perfect fit.

Werner can activate an exit clause in his contract until 2023, which allows him to leave Leipzig this summer for a sum in the region of 60 million euros (US$66 million).

Statements made by his management team indicate Werner couldn't get over the disappointment of Bayern's eventual disinterest last year after prolonged negotiations over a move broke down.

Last season Werner appeared to be one of European soccer's potential bargains, with a price tag of 25 million euros.

After the breakdown in the Bayern talks, Werner extended his contract at Leipzig to include the exit clause.

Bayern supposedly viewed Werner as a potential backup or strike partner for Polish target man Robert Lewandowski－regarded as a very similar player to Werner.

For the time being, it seems like Serge Gnabry and Thomas Mueller will continue to alternate as Lewandowski's attacking foil, with Sane eventually boosting Flick's options if a deal can be reached with City.

Bayern's chairman-designate Oliver Kahn, who has emphasized that the club will only sign new faces if they fit the team's philosophy, is said to be playing a key role in the Sane negotiations. Approval for the deal is expected within weeks.

Meanwhile, Bayern officials are anxiously waiting for the German government to allow games to be played behind closed doors by mid-May. The Bundesliga was suspended on March 13 due to the coronavirus pandemic but, like all German clubs, Bayern is keen to complete the 2019-20 campaign so the season can contractually finish by June 30.

Bayern is bidding to seal a 30th domestic top-flight title and a sixth Champions League/European Cup crown. It currently leads the Bundesliga by four points ahead of second-place Borussia Dortmund with nine games left, and leads Chelsea 3-0 from the first leg of their Champions League last-16 tie.

German Interior Minister Horst Seehofer on Sunday backed a possible restart for the Bundesliga season this month without spectators.

Bundesliga clubs have returned to training in small groups and the government is due to decide this week on a potential resumption of sports activities.

READ MORE: Bayern faces crucial decision of signing either Sane or Werner

The German Football League (DFL) has submitted a health-and－safety plan for games without spectators which includes regular testing of players but no quarantine for entire squads in cases of positive tests. "I find the time frame of the German Football League plausible and I support a restart in May," Seehofer told Bild newspaper.

"But for me it is also clear that there should be no extra privileges for the league."

He also said he was in favor of fullteam quarantines in cases of positive tests, something that is not planned in the DFL blueprint.

"But I am in favor of trying to attempt to play again," he added.