The high court in Johannesburg was expected rule on Monday on whether Czech businessperson Radovan Krejcir would be moved from jail to hospital.
His lawyers filed an urgent application with the court on Sunday requesting that Krejcir be moved from jail to hospital.
They claimed that Krejcir was assaulted following his arrest on Friday.
Judge Ramarumo Monama on Monday reserved his judgment.
"Judgment in this matter is reserved to [later on Monday]," Monama said shortly before 1am on Monday morning in the high court in Johannesburg.
The verdict was expected to be delivered at 11am.
Monama heard testimony from Krejcir's doctor, a state doctor and a police official.
Krejcir's doctor, who can not be named for security reasons, recommended that he be hospitalised. He said Krejcir could face renal failure if he did not get medical attention.
Medical attention in jail
The doctor said the injuries suffered by Krejcir were consistent with those of someone who was assaulted.
The state also called its own doctor who claimed that he observed injuries on Krejcir wrists. He claimed these could have been caused by the handcuffs.
The state argued that Krejcir could receive medical attention in jail.
Meanwhile, Krejcir and a co-accused were expected to appear in the Alberton Magistrate's Court for kidnapping and attempted murder charges.
It was not known how the latest developments would affect the appearance.
Breakthrough for SAPS
National police commissioner Riah Phiyega said on Saturday that the arrest of Krejcir was a major breakthrough for the South African Police Service (SAPS).
"There are many investigations that are taking place, even on the charges that the suspects have been arrested for. We hope to arrest more suspects as the investigations unfold," she told reporters in Pretoria.
"It took us a long time to work on this matter … I thank the SAPS multi-disciplinary teams."
Phiyega said Krejcir and an associate would appear in the Alberton Magistrate's Court on Monday.
State would oppose bail
The police chief repeatedly stated that the state would oppose bail, should Krejcir apply for it.
"We will be in court on Monday, and should there be an application for bail, we shall oppose it," she said.
"We will also be looking at any involvement of our own members."
The name of Krejcir's associate, who was arrested with him on Friday, would only be disclosed in court.
"I would not like to say in public about the name of the associate. On Monday, when we put our case [in court], the name of the associate will be made public."
Phiyega on Saturday said an initial charge of assault with intent to do grievous bodily harm was reported against Krejcir in the East Rand.
However, given the severity of the assault, the charge would be changed attempted murder.
Details of the complainant
"Regarding the issue around attempted murder, indeed when you talk about cause [to do] grievous bodily harm we would say there is a case for attempted murder. We probably will look into those when we deal with this matter in court," said Phiyega.
She would not mention the details of the complainant, other than saying "it's a South African male from the East Rand".
Phiyega said the assault happened in June. – Sapa