With the South African sporting hero already facing a tough fight to win bail, the prosecution presented police evidence to flesh out the charge he deliberately murdered the cover girl on Valentine's Day.
Police investigator Hilton Botha told the court that an unnamed witness "heard talking that sounded like non-stop fighting from two to three in the morning" shortly before Steenkamp was found dead at Pistorius's Pretoria home last Thursday.
Botha also said 29-year-old Steenkamp was shot three times through the bathroom door, with wounds to her head, elbow and hip.
Botha said the shots were not fired straight at the toilet door, but rather "directly to the toilet, the basin itself."
"If you walk in directly and fire straight at the door you will miss the toilet," he said, suggesting Pistorius had been aiming.
Steenkamp, who had been going out with Pistorius since late last year, was declared dead shortly before 4:15 am on February 14 by medics and was found covered in towels and wearing white shorts and a black vest.
Botha also said 26-year-old Pistorius would face an additional charge of possessing unlicensed .38 special calibre ammunition. At Tuesday's hearing, the Olympic and Paralympic track star had tearfully denied premeditated murder, a charge that risks a life sentence.