Monaei De'Viana, now 21, claims her father spat at her as she was driven back from a tennis tournament "because he considered she had not performed as she had ought to", Mr Povall said.
Nephe, now 19, recalled having been hauled off the courts and "kicked and punched" by Mr De'Viana behind a curtain because he was unhappy with her performance.
"It is the Crown's case that, over a period of years, he made the lives of his two daughters miserable in a variety of different ways, but primarily around his ambition that they should be rich, famous and successful tennis players," Mr Povall said, according to a report published in the UK Telegraph.
"Mr De'Viana had a background of competing in karate at quite a high level and, as his eldest daughter Monaei got older and got into primary school, he started to train her in tennis and from quite a young age was taking that quite seriously, coaching her himself for some hours of the day.
"When Nephe got to about the same age, he started with her as well."
Mr Povall was giving his opening address in the trial of Mr De'Viana, who has denied two counts of cruelty to a person aged under 16.
The court heard Mr De'Viana took each girl out of school at the age of 11 to make more time for his tennis training sessions, which would begin at the crack of dawn and end when the girls fell into bed exhausted at the end of each day.
"He subjected them to a tough, rigorous and demanding training schedule of stretching, physical exercise and technical tennis training," Mr Povall told the court, the Telegraph reported.
"In itself, there is nothing wrong with that. We all know, or have been ourselves, pushy parents, and where there is a child who shows talent then it is not surprising or wrong that their parents should encourage them, discipline them and help them make the very best of that talent.
"However, it is the Crown's case that John De'Viana's behaviour went beyond that. It went beyond the mother of the Murray brothers, who was a demanding parent and got them to the very highest level in tennis.
"John De'Viana behaved in a way that went so far as child cruelty as the law defines it, that is, he assaulted or ill-treated his children over time so as that the cumulative effect was likely to cause them unnecessary suffering or injury to health.
"He did that, on the Crown's case, by way of physical assaults and mental abuse of those girls, relentlessly over a period of years."
The court heard Mr De'Viana's abuse of Monaei was "more verbal" while Nephe suffered more physical attacks.
"They both say that, on occasions, they were forced to run round and round the tennis courts. Nephe said that went on for hours at a time," Mr Povall said.
"The best examples of the sorts of things they experienced were a daily torrent of verbal abuse, that they would be called 'motherf**ker' and 'c**ts' and 'fat, lazy c**ts' by their father when he was dissatisfied with the way they were training.
"That they would be subjected to physical assault, particularly Nephe: he would take her out of sight if he was unhappy with her and kick and slap her.
"That there were occasions when he was serving balls at them in order to punish them for the way they had trained poorly. That he would do things in order to humiliate them as punishment if he was cross with them.
"Nephe, for example, a talented young tennis player, got some sponsorship and got a rather smart tennis bag. As kids will be, she was very excited about it. But she was told: 'No, you have not earned that'.
"There were times when she was forced to go to tournaments or sessions carrying her kit in a black bin bag."
Mr Povall said Mr De'Viana's behaviour would be "particularly unpleasant" if he felt his daughters had played badly in tournaments.
"Monaei describes being driven back from a tournament and being spat on as he was driving because he considered she had not performed as she had ought to," he told the court.
"Nephe said he would always be in coach mode. In other words, this was not an occasional blow-up, a loss of temper. Every parent loses his or her temper sometimes.
"But, as far as their lives were concerned, this was relentless, from 5.30 in the morning through to going to bed when they finished training and stretching."
Mr Povall said the girls were "being deprived of food at lunch time, not being allowed to eat the packed lunch they were given because they were not trying hard enough".
"One of the girls was dragged off an exercise bike because she was timing her session with her phone rather than a watch," he said.
"His obsession with their success meant that this sort of behaviour, this sort of barracking he gives was constant."
Nephe told the court how her father made her run around a court for up to seven hours without a break in a bid to make her a star.
She described one incident in which her father took her off court behind a curtain and punched and kicked her with his hand over her mouth to stop her screaming.
The trial continues.
