The attacker behind the Van Breda axe murders possibly dragged and shoved Rudi's body around to show his anger, blood spatter expert Captain Marius Joubert testified on Thursday.
During cross examination by Advocate Pieter Botha over what triple murder accused Henri van Breda would gain from moving his 22-year-old brother from where he was attacked on the bed, Joubert conceded that he didn't know.
"There was a lot of anger towards Rudi, in my opinion," Joubert told the court.
"It is possible that the attacker showed his anger by dragging and shoving his body around."
Rudi was according to State witnesses and evidence the first to die.
Pathologist Dr Daphne Anthony in her testimony postulated that Rudi's injuries showed he had been lying on the right side of his face. Trauma to head means he was aware of what was coming and had raised his hand in an attempt to ward off the attack, resulting in incised defensive wound on little finger.
Drops of his blood were also found on the neighbouring outside wall, from a hard blow which had ostensibly resulted in blood spattering through the window.
Van Breda, 22, pleaded not guilty to axing his parents and brother to death, seriously injuring his sister Marli, and defeating the ends of justice.
He alleged that an intruder wearing a balaclava, gloves and dark clothes was behind the attack and that he had heard other voices of people speaking Afrikaans in their multi-million rand home on the highly-secured estate.
Van Breda claimed that, after a fight with the axe-wielding intruder who was also armed with a knife, the man had escaped.
Henri in his plea explanation had claimed that he had disarmed the attacker and thrown the axe at him as he pursued him down the stairs of their De Zalze Estate home.
Joubert found this unlikely, explaining that the damage to the staircase wall was caused by axe being hit, not thrown, from only 1.5m away.
He demonstrated how Henri would have been close enough to wield the axe at the intruder.
"Why would you throw an axe at someone when you can hit them directly with it?" he asked.
Botha, however, asked if Joubert had known Henri's position, how many rotations the axe had made or how hard it had been thrown. Joubert conceded that he didn't.
Henri also could not recall where on the stairs he had been at the time of hurling the axe.
The trial resumes on Monday.