Novak Djokovic has expressed his heartache for Boris Becker after his former coach was jailed for two-and-a-half years.
German legend Becker was sentenced to jail in London on Friday for hiding $4 million worth of assets and loans to avoid paying his debts.
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After retiring as a player, Becker turned to commentary and coached Djokovic for three years starting in December of 2013.
Speaking ahead of the Madrid Open on Sunday, Djokovic told reporters: "Just heartbroken for him.
"He's a friend, a long-time friend, a coach for three, four years, someone I consider close in my life and has contributed a lot to my success in my career.
"I'm not going to get into details of the verdict, because I'm not in a position to do that, but, as his friend, I'm super sad for him.
"It's not much that you can say.
"I just hope he will go through this period that he has to be in jail and that when he comes out he's able to live his life - I don't know if we'll use the word 'normal' because life is definitely changing for anybody going to prison, especially for that long of a time.
"I don't know how things will turn out for him. I just pray for him.
"I hope things will be well in terms of his health, his mental health, because that's going to be the most challenging part."
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Djokovic has endured his own tumultuous time of late, including being deported from Australia before the Australian Open due to his refusal to get vaccinated against Covid-19.
He will contest just his fourth tournament of the year this week in Madrid having reached the final on home soil in Belgrade last weekend.
"Of course I have never experienced anything similar to what I experienced at the beginning of the year, and I did not know how that's going to affect me," he said, admitting some mental scars remain.
"I still have to deal with it to some extent. It's not as powerful that it was in the first two, three months of the year. I feel like the more I play, the more I'm in this environment, the more comfortable I feel.
"I'm happy that I'm back on track in terms of being able to play in tournaments and having clarity in terms of schedule.
"So hopefully I will be able to get the best out of myself, particularly in grand slams."
Becker was convicted of four charges under Britain's Insolvency Act in April, including failing to disclose, concealing and removing significant assets following a bankruptcy trial.
The six-times grand slam champion was found guilty of transferring money to his ex-wife Barbara and estranged wife Sharlely after his 2017 bankruptcy.
"It is notable you have not shown remorse or acceptance of your guilt," judge Deborah Taylor told him on Friday as she sentenced the two-time Australian Open champion at London's Southwark Crown Court.
"While I accept the humiliation you have felt as a result of these proceedings, you have shown no humility."
The judge said Becker would serve half his sentence behind bars and the remainder on licence.
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