Ivan Klasnic always knew what he wanted. As long as he was working towards a goal, he felt he was in control, no matter how big the challenge. When faced with choices, his decisions were swift and resolute. Like when, at the age of 21, he had to pick a national side to play for. Germany, the country of his birth, offered a chance to play in a World Cup on home soil. Bosnia-Herzegovina, where his parents and ancestors hail from, would have built a whole team around him. But it was never really a contest. His mind was made up early. While neither he nor his parents may ever have lived there, Klasnic is an ethnic Croat and that is Croatian blood coursing through his veins.

The Werder Bremen striker had made that very point at the time of his decision. And that is why it is so ironic that now, three times a week, that very same blood must travel through a dialysis machine to be cleansed, because Klasnic’s own kidneys are unable to do the job. The striker suffers from a rare kidney ailment, first diagnosed in September 2005, when he had a routine appendix operation.

The doctors initially told him that it could be treated with a cocktail of drugs and that, most likely, his kidneys could be saved. Buoyed by that hope, he went to the World Cup finals and played on with Bremen. But, by December last year, it became obvious that medical science had been wrong. His kidneys were not getting any better. In fact, they had deteriorated to the point that they were no longer functioning properly. The blood of which he was so proud was coursing through his veins unclean and soiled. He needed a new kidney.

“It was a huge blow when I heard the news, but I can only think that it happened for a reason,” he said at the time. “God gave me this challenge, but he also gave me the tools to overcome it.”

Klasnic’s “tools” were his family members, who immediately closed ranks around him. Kidneys are not easy to come by. One route is to sign up to receive a kidney from a recently deceased donor, but that can take years. At 27, Klasnic could not wait, not if he wanted to resume his football career. The alternative is to receive a kidney from a live donor. Nature, in its wisdom, gave each of us two and most people can lead normal lives with one, which means that most of us have the ability to donate one of our kidneys to save a life.

In that sense, Klasnic was blessed. His mother, Sima, his brother, Josip, and his wife, Patricia, all volunteered to donate one of their kidneys. Doctors told Klasnic that, provided there was a match in terms of blood type and other parameters — and, in the case of family members, there usually is — there was a 90 per cent chance that the transplant would be successful. There was even talk of him returning to football by April.

Sima went under the knife on January 24, but cruelly, on the day he was to celebrate his birthday, the doctors told him that his body had rejected his mother’s kidney. Again, Klasnic turned to God. “There must be a reason for this,” he said. “We are being tested, but we are strong and united and we will overcome it.”

His brother Josip, a dentist, is next up. In the next few weeks it will be his chance to give part of his body to save a life. And if that fails, Patricia, his wife, will follow.

“I’m ready,” she said. “If it comes to me, I’ll do what is necessary. When we heard the news [that Klasnic had rejected his mother’s kidney] we felt we were in hell. But we soon realised we were ready to push on and keep fighting.”

It is no longer just about football, but the question of whether Klasnic will ever play again remains. Bremen, in a gesture of goodwill, have extended his contract by another season. The doctors, as ever, refuse to make promises. They say that if his body accepts a new kidney, his recovery should be no different from that of most patients, who return to work in six to eight weeks without any significant consequences.

Of course, for most people, going “back to work” does not mean returning to competitive sport, with the lung-busting runs, crunching tackles and daily wear and tear. And yet Klasnic can draw strength from the fact that a handful of other athletes have come back from a kidney transplant. Norberto Oberburger, the Italian weightlifter and Olympic gold medal-winner, won a world title after surgery. Alonzo Mourning, the basketball player, won his first National Basketball Association championship two years after receiving a new kidney. Jonah Lomu returned to competitive rugby union after a kidney transplant.

Thus the examples and inspiration for an amazing comeback are there, though the odds are stacked against him. Whatever happens, his family — with their self-sacrifice and love — have already proved that he is truly blessed.

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