In his heyday as the world's top tennis player, Boris Becker was renowned, above all, for his tenacity. But yesterday in a Munich courtroom, the three-times Wimbledon champion was faced with the prospect of a humiliation no amount of effort on his part could avert.

Across the room, a state prosecutor was calmly explaining how long he wanted to see Becker jailed for on each of the counts in the indictment for tax fraud he had earlier levelled at Germany's pre-eminent sporting idol.

The total - three years and six months - drew gasps from the press benches and the public gallery. It was almost twice the highest estimate floated in the run-up to Becker's trial. But, said Matthias Musiol, the 34-year-old former champion had refused to admit his guilt until taken to court, and dragged his feet on paying back taxes.

"The payment was made seven years after the fact and one week before his trial - at the last minute, so to speak."

Becker, who had dyed his hair almost white for his trial, stared at the prosecutor with ill-concealed frustration and annoyance. Even his lawyers have acknowledged the substance of the prosecution's case - that, while claiming to be resident in Monte Carlo, their client had really been based in Munich.

"We admit that a domicile did exist in Germany at the time of the alleged offence," one of his legal team said.

But yesterday Becker hurled himself into his own defence with a startling claim that he had been hounded out of his sporting career by Germany's tax sleuths.

"Tennis is a very psychological game and you have to be free of fears and worries about what will come your way next," he told the court.

He had earlier described a 1998 raid on his Munich home, where his parents were living at the time. His father, already suffering from the cancer that was to kill him, was kept in the house for six hours and prevented by the tax inspectors from going to an appointment with his doctor, Becker said.

"I gave \ up a short while later because I could not go on that way," he added.

In a statement to the court, the retired tennis star said: "I admit that I made a mistake 10 years ago and I know that I will have to pay the consequences for that." But, he protested: "I cannot be accused of hiding money, working 'on the black', concealment or any other criminal act."

In the early 1990s - when he is accused of dodging $1.6 million in taxes - "I had tennis on my mind - and now and then girls," he said.

The hearing soon came to focus on a house rented by his sister, who works as an architect in Munich. The prosecution maintained that it had been found in 1991 by estate agents commissioned by Becker as part of a "clear and conscious" ploy intended to let him return to Germany without paying German taxes.

Becker, who was then at the height of a sporting career that netted him $23 million in prizemoney, said he merely stayed odd nights in a "spartan flat" in the attic "that had just a bed and a sofa but didn't even have a refrigerator."

But he visited Munich with growing frequency after he fell in love with Barbara Feltus, the American-German model who was to become his wife. The indictment claimed that in 1992 and 1993, he spent almost twice as much time in Munich as in Monte Carlo. Key evidence against him was a list kept by his mother, showing his whereabouts.

Asked about the list, Becker moved the presiding judge, a woman, to laughter by remarking: "Mums know a lot, but they do not know everything. I was not always where my mum thought I was."

His junior counsel asked for probation for his client, which would be a maximum of two years under German law. Jorg Weigell said Becker was not the one who gave false information about his finances. "His advisers did that," he said.

Professor Klaus Volk, who led for the defence, told the judges that no purpose would be served by locking his client up. A verdct is expected this morning.

- Guardian Service