Continuing his ruthless questioning, Mr Nel, known as the 'pit bull', challenged the athlete's claim that the crime scene was contaminated and objects, including the fan and the duvet, were moved by the police after they arrived at the scene.
The position of the duvet, and in particular the large tripod fan, as shown in the crime scene photographs, which he insists was altered, would have blocked him en route to the balcony, where he claims he called for help after shooting Ms Steenkamp, and contradict his version of events.
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"You see Mr Pistorius, it was never moved, that door was open when you and the deceased got into an argument, the fan was there, the duvet was there, the curtains were in that exact position, nobody moved anything," Mr Nel told the court, launching his case.
Photo / AP
Large fan and duvet would have blocked Pistorius's way en route to the balcony where he claims he called for help the night Reeva Steenkamp died. His defence claims the crime scene was contaminated and objects moved. Pistorius's defence counsel, Barry Roux, objected to Mr Nel's claim that there was an "argument" in the run-up to Ms Steenkamp's death, telling the court there is no evidence to support his claim.
Mr Nel insisted the "only reasonable inference is that the deceased ran screaming from there, that's why we heard screams, and the door was never closed", to which Pistorius immediately replied: "that's not true".
Earlier in his evidence, the athlete claimed the duvet was on the bed when he got up and remained on the bed when he sat on it in the early hours of 14 February to put on his prosthetic legs after shooting his girlfriend thinking she was an intruder. He also claimed the curtains were moved open.
Watch: Tough cross-examination
"Your version is a lie, you never closed that curtain in the first instance, that's why you have to come up with these things," Mr Nel told the court. "Now we have to look for a policeman that moved the duvet to the carpet, that moved the fan back, that moved the curtains more open, those three things am I right?"
The chief prosecutor argued Pistorius's version of events is "so improbable nobody would ever think it's reasonably or possibly true", adding: "You're trying, but it's not working".
Pistorius denies murdering Ms Steenkamp, claiming he shot and killed her in a case of mistaken identity thinking she was an intruder after he heard the noise of a "window sliding open" and a door slamming shut, which convinced him someone had entered his house in the early hours of 14 February.
There are no juries at trials in South Africa and Pistorius's fate will ultimately be decided by Judge Masipa, assisted by two assessors.
The case continues.
- UK Independent