Photo credit: AFP

Bayern Munich director of sport Mathias Sammer has threatened legal action over reports Arturo Vidal has an alcohol problem and defended Pep Guardiola’s decision to coach Manchester City next season.

The worst kept secret in football was confirmed on Monday when the 45-year-old Guardiola announced he will replace Manuel Pellegrini at City in a deal reportedly worth more than £15 million ($21.5 million, 20 million euros) a year.

Sammer says the club will take action against claims Vidal was drunk during their January training camp in Qatar and will pull together, despite Guardiola’s news coming in the middle of an injury crisis.

The latest turn of events comes after an unnamed Bayern player told magazine Kicker last week that the spirit is “not good” in the star-studded squad after Guardiola demanded more professionalism from his players.

“Our coach is currently being made responsible for everything (by the media) and what is going on here at the moment isn’t right,” Sammer fumed to reporters in Wednesday’s volatile press conference.

“Guardiola has never claimed to be perfect, but I am impressed with the intensity with which he lives and loves football.

“And I am asking for a bit more respect — and not to make things so personal.”

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Both magazine Sport Bild and Munich-based newspaper TZ claim Vidal repeatedly left the team hotel in Doha, during last month’s training camp, and was intoxicated on his return, something which Sammer furiously denied.

“Arturo is in very, very good form and I was surprised about what I read. It’s not true, that much is clear,” said Sammer.

“We have a very good, close relationship with Arturo and he himself has said there is no truth in it at all.

“Perhaps there are those trying every means (to stir up trouble) against FC Bayern to make the league more exciting.

“I can only say, you will achieve the opposite.

“We will just pull tighter together and become even more unified.

“In the case of Vidal, we will proceed by legal means.”

Sammer also revealed that new signing Serdar Tasci had to sit out Wednesday’s planned introductory press conference after suffering concussion in his very first training session — less than 48 hours after signing for the Bavarians.

Germany international Tasci, 28, only signed a six month loan deal from Spartak Moscow on Monday as emergency cover after the Bavarian giants were plagued by a run of injuries in defense with Javi Martinez, Jerome Boateng and Medhi Benatia all out.

SEE MORE: Pep Guardiola ready for risk with Manchester City.

Bayern coach Guardiola has just one fully-fit centre-back in Holger Badstuber.

Tasci faces a race against time to be fit for Saturday’s German league match at fourth-placed Bayer Leverkusen and while Sammer admits all is not rosy in the Bayern camp, he says the pressure will only pull the squad together.

“One thing is clear: FC Bayern and ‘calm’ don’t fit well together, even when we win every game,” he said.

“I don’t want to say that things aren’t crackling (with tension) here at the moment, but there are certain trigger points and we have to up the ante at Leverkusen on Saturday.”

Bayern face Leverkusen as runaway leaders, eight points clear in the German league table.