'I watched my father killing my mother'

The Polish winger encountered a fork in the road very early in his life: he was ten years old when he and his brother witnessed his father brutally stabbing their mother to death. It happened after a heated argument and the murderer was sentenced to 15 years in prison. Kuba never spoke to his father again, although he did attend his funeral after he died at the age of 56.

The trauma forced him to give up football for some time, but he admirably rebuilt his life. Kuba started off at Wisła Kraków, and now plies his trade at Wolfsburg. He has struggled through injury early in the season, but has still made nine appearances. He also played for Fiorentina after living his best years at Borussia Dortmund.

He was a key player in Jurgen Klopp's Dortmund side that reached the Champions League final and were twice crowned Bundesliga champions. He started in the European final against Bayern Munich, but were defeated despite boasting the likes of Lewandowski, Hummels, Gundogan or Gotze in their ranks.

"In my autobiography, I reveal everything that’s happened to me, including when at the age of 10, I witnessed the murder of my mother by my father," he said in January 2015.

"I will never understand why it happened. I’ll always ask myself ‘Why?’," said the footballer, who was made stronger by the saddest day in his life. "It’s not easy, but it’s an episode I haven’t forgotten and will never forget; that day, my life was changed forever. But I think it also gave me lots of strength. I’ve had to deal with so many adversities in my life, that others would never have been able to."

"Earlier in my life it was something I never wanted to mention. I tried to forget it but I couldn’t. But now I am mature enough to speak about it. Until the end of my lifetime I will have to live with this."

"My mother is looking after me. I have had some difficulties in my life but I have overcome all of them and I feel it is because she is somewhere and helps me. Without her I could be on a wrong way in my life. I try to make her proud because she did great things for me and my brother."

In a few months, he will be in Russia. It will be his first World Cup after featuring in two European Championships. "I never let anything get the better of me," he concluded. "I always know I’ve already lived through worse."