Oscar Pistorius sentence is underway at the North Gauteng High Court in Pretoria, with the disabled South African athlete facing a potential ruling of up to 15 years in jail. However, a possible verdict by Judge Thokozile Masipa was described by prosecution as "shockingly inappropriate."

The 27-year-old was found guilty of culpable homicide in early September for shooting his girlfriend Reeva Steenkamp, a law graduate and model, on Valentine's Day in 2013, according to The Week.

After his lawyers began anew with prosecutors over the severity of his punishment, Oscar Pistorius sentence is once again being negotiated. He returned to a Pretoria courtroom on Monday.

According to the New York Times, if convicted of premeditated murder, the Paralympic runner who competed against able-bodied athletes at the 2012 London Olympics, would be facing mandatory minimum jail term of 25 years.

But Masipa found him guilty of the lesser charge of culpable homicide during Oscar Pistorius sentence on Monday, which is the equivalent of manslaughter. He was also found guilty of one charge of negligently discharging a firearm in a crowded restaurant in Johannesburg in January 2013, even after he admitted shooting 29-year-old Steenkamp to her death.

The athlete's defence team seeked leniency from Masipa during the latest Oscar Pistorius sentence, calling witnesses who described him as "a broken man." His punishment was also proposed to be limited to house arrest and community service, which the prosecution said is "shockingly inappropriate."

The defence's three witnesses is expected by the court for Oscar Pistorius sentence. An official witness from South Africa's Department of Correctional Services is expected as well. Meanwhile, the whole process of Oscar Pistorius sentence is likely to end before the week is done.

A state official testifying for the defence recommended on Monday that Oscar Pistorius sentence for killing his girlfriend should involve mopping floors two days a month for the next three years.

The "shockingly inappropriate" recommendation, together with house arrest, was the offer Monday during Oscar Pistorius sentence of culpable homicide during which witnesses testified at the North Gauteng High Court.

Social worker Joel Maringa from the South African Correctional Services reportedly gave his report to the court. He said he believes Pistorius should not "be destroyed" and the Oscar Pistorius sentence should focus on his rehabilitation rather than retribution.

However, prosecutor Gerrie Nel told Maringa his recommendation was "shockingly inappropriate" for the severity of the crime Pistorius had done.

There were even several occasions when Nel confronted Maringa and asked if he read the judgment on Oscar Pistorius sentence. Meanwhile, Maringa groped through his answers. At one time, he had the firearm charge confused with the culpable homicide conviction.

Although Maringa admitted he wasn't aware that Pistorius used Black Talon ammunition and that four bullets were fired during the shooting, he said he read "somewhere that he didn't mean to shoot the deceased."

At that time during the hearing on Oscar Pistorius sentence, Nel seized the moment and said, "No, you are wrong. That is not what the judgment says. Did you even read the judgment?"

Maringa continued suggesting that an appropriate Oscar Pistorius sentence for Pistorius would be 16 hours of community service at the Transvaal Museum or Little Company of Mary hospital in Pretoria, where Pistorius would be doing "cleaning duties."

He added that Oscar Pistorius sentence should be involve house arrest at his uncle's house, which ironically is a 24-room mansion in the upper class suburb of Waterkloof, and home to many embassies and diplomats, including the U.S. ambassador, reports the New York Daily News. Maringa further went on to say that the athlete should be allowed to continue with his sports career.

"But the judgment says he was grossly negligent, surely you should have taken the seriousness of the crime into account," said Nel.

"I did, but he was not convicted of murder, but of culpable homicide," Maringa rebuked.

Clearly frustrated, Nel eventually threw up his hands and told Maringa his findings for deciding on Oscar Pistorius sentence were based on the wrong set of facts.

Pistorius' therapist Lore Hartzenberg also went to the court and said the paralympic athlete was a "broken man" who lost everything since the "accidental" killing.

"He has lost his love, he has lost his career, he has lost his friends and his earning potential," said Hartzenberg as she faced the court. She added that some sessions simply had Pistorius "crying and me holding him."

The third witness was Pistorius' agent Peet van Zyl. He said after the shooting, the 27-year-old lost all his sponsorship contracts. He also went further to say that Pistorius was a man who did charity work, including for the Laureus Foundation, UNICEF and for sponsors Nike, Thierry Mugler and Oakley.

The killing on Feb. 14, 2013 was a mistake, said Pistorius. He reportedly thought an intruder had entered his home, thus firing four rounds from a handgun through a locked toilet cubicle door, and later on discovered that Steenkamp was inside.

Prosecutors have previously said they will push a harsher Oscar Pistorius sentence, since he had been grossly negligent in firing four times into a locked bathroom door.

Meanwhile, Nel is convinced that he killed Steenkamp deliberately after a quarrel. However, Judge Masipa rejected the this argument to be included as basis for Oscar Pistorius sentence. Both sides will still be able to appeal her decision.

The hearings adjourned early until Tuesday by Nel's request.

The case of Oscar Pistorius sentence has many fascinated especially with the athlete's track achievements despite physical challenges.

The hearing has also been confronted by many South Africans with worrisome questions about the nature of justice in their society which is still driven by racial distinctions.

Oscar Pistorius sentence, in the end, is entirely up to the judge's decision. Initially set to last three weeks, the trial began in March and has already gone through several dramatic moments and frequent delays.