Then Bayern Munich's German head coach Jupp Heynckes and his players celebrate on the balcony of the city hall in Munich, southern Germany on May 20, 2018. (GUENTER SCHIFFMANN / AFP)

BERLIN - Jupp Heynckes might have retired from his life as a football coach, but with his 75th birthday approaching this Saturday, many fans remember one of Germany's most successful footballers and coaches.

Hordes of birthday cards are arriving at the two-time Champions League (Real Madrid/Bayern) winner's refurbished farmhouse in Schwalmtal located between the Dutch border and his hometown Moenchengladbach. They are a sign of the admiration and respect with which he is held.

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As an official, I would rather count on the players I already have instead of buying new ones

Jupp Heynckes, Former coach of Bayern Munich

The 1975 Euro League winner speaks of a lovely gesture of a Chinese fan living in the German city of Wuppertal. "He sent me 50 protective masks for my wife and myself. He told me to wear it as it can help block the virus," the former coach said.

"I replied with a Bayern shirt with autographs and a German national shirt," he said. Heynckes was talking about lots of letters he has received from China ahead of his birthday. He said he is deeply moved by the solidarity and the greetings from China.

Capped 39 times, the former striker (243 league goals) may have left the coaching bench after winning the 2013 treble as the first German manager but is still following football intensively.

The 1974 world champion suggested football clubs should do without expensive stars due to the coronavirus crisis.

"I would count on promising younger talents," the 1972 European champion said in a recent interview.

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 on July 27, 2019. (CHARLY TRIBALLEAU / AFP)

The former manager said over 100 million euros for Manchester City star Leroy Sane is far from a reasonable amount of money. "From my perspective, Sane hasn't yet achieved his breakthrough to become a world class player."

Clubs have to change their financial approach "as even well-balanced clubs might get into difficulties unlike any other before". Heynckes demanded today's professionals accept wage cuts to keep the system running on a new basis.

"As an official, I would rather count on the players I already have instead of buying new ones," he emphasized.

The developments in football have been immoral.

"We need solidarity in all parts of society, and we should rethink our lifestyle in general," he underlined. He said he is busy thinking about the world's future as significant challenges lie ahead of humankind, such as climate change and food supply.

He said he hopes football continues despite "games behind closed doors being terrible. But this way seems to be the only one with a chance." Clubs have to consider playing the entire upcoming season without fans.

Heynckes called quick solutions inevitable to secure football's future. "We need to save football right down to the bottom leagues."

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After the crisis, clubs have to be aware that fewer fans than usual will be able to spend 110 euro on a ticket, he said. Sponsoring income is going to decrease as merchandising profits will drop.

Football is well advised to consider its social responsibility, commented the former Bayern, Real, Schalke, Leverkusen and Bilbao coach. The sport should get back to its roots and concentrate on its traditional purpose.