Pistorius' agent was forced to cancel all future races, he said, so Pistorius could concentrate on defending himself against allegations he murdered his model girlfriend by shooting her several times in his upscale house on Valentine's Day morning.
Reeva Steenkamp died from gunshot wounds suffered inside Pistorius' home in the predawn hours of Thursday. Pistorius was arrested and charged with her murder the same day. His family denies he murdered her.
"I have decided that following these tragic events that we have no option but to cancel all future races that Oscar Pistorius had been contracted to compete in," agent Peet van Zyl said in a written statement late Sunday night.
A few hours earlier, Van Zyl had visited his athlete at a police station in the South African capital, Pretoria, where he is being held in custody in a red-bricked, one-story building with green metal fencing.
Pistorius has been there since Friday following the shocking developments at his villa in a gated community in Pretoria's eastern suburbs where Steenkamp was shot dead.
Her death and Pistorius' arrest stunned South Africans, who revered Pistorius for his humble nature and success at overcoming adversity to become an international star, despite having his lower legs amputated as a baby.
Pistorius still had "overwhelming support" from his fans, Van Zyl said as he left Brooklyn police station, but the agent steered away from a question from a reporter on what Pistorius' emotional state was now like following the death of his girlfriend and a possible realization that his entire career was in ruins.
Pistorius' sponsors -- including big-name brands Nike and eyewear manufacturer Oakley -- were also sticking by him, Van Zyl said. But that could depend on the outcome of a possibly lengthy murder trial.
"Regarding sponsors and partners, I can confirm that at this point in time, all parties are supportive and their contractual commitments are maintained," Van Zyl's In Site Athlete Management company said. "They have said they are happy to let the legal process takes its course before making any change in their position."
The Beaverton, Ore-based Nike Inc. and Foothill Ranch, Calif.-based Oakley Inc. did not immediately respond to messages from The Associated Press seeking comment.
Pistorius was quickly arrested and charged with murder Thursday, with prosecutors saying at his first court appearance a day later that they would pursue a more serious premeditated murder charge, which carries a life sentence.
Pistorius broke down and wept in the court, with his face in his hands. His family later denied he murdered Steenkamp and said the state's own evidence "strongly refutes" any possibility of a murder.
"I am not going to comment on anything except that (what) is related to his athletics career at this point in time," Van Zyl told reporters outside the police station after being asked how Pistorius was coping. "Obviously from a management side and also as a friend, it's a tragic circumstance and events that have unfolded and we can only give Oscar our support at this point in time."
Family members and his lawyers also visited Pistorius on Sunday, but declined comment both when they arrived and when they left the city center police station.
The family of Steenkamp, a model, law graduate and budding reality TV star, told The Associated Press that her body had been released by police after an autopsy and was back in their hometown of Port Elizabeth on South Africa's southern coast.
"Reeva is back home," the late model's brother, Adam Steenkamp, told the AP by phone. He had flown back from Britain, where he now lives, to be with the family.
They also said Steenkamp's funeral would be held Tuesday and would be a private ceremony for family at a local crematorium. Media would not be allowed in.
The main purpose for Van Zyl's visit to Brooklyn police station Sunday afternoon was to discuss Pistorius' running career, but "also to visit him as a friend and give him my moral support," the agent said. "On a personal level I wanted to offer my support to Oscar, who I have known and worked with for the last seven years and consider a friend and a great professional athlete."
Following the meeting, Van Zyl announced publicly that the five races that Pistorius had confirmed for in 2013 were canceled: two in Australia in March, exhibition races against fellow Paralympic champions Alan Oliveira of Brazil and Jonnie Peacock of Britain, and an appearance at the U.S. Drake Relays in Iowa.
Van Zyl's decision to cancel those races was first reported by the AP on Saturday. All others that were still in negotiation were also now called off, Van Zyl said on Sunday.
The high-profile rematch with Oliveira, who beat Pistorius in the 200 meters at the London Paralympics last year, was to be a straight line 200 race on Copacabana beach to promote the 2016 Rio Olympics and Paralympics.
The runner's main goal for 2013 was to qualify for the worlds in Moscow in August, which is now almost certainly not going to happen.
Pistorius was the first amputee athlete to run at the world championships in 2011, then made history when he competed at last year's Olympics in London.
He and his coach have both said that they aimed to retire from track after the Rio Games, but one of the world's most famous athletes, who fought for years to be allowed to run against able-bodied competitors, is now facing the possibility he will never go to any major meet again.