Oscar's agent shows he's no Jerry Maguire

Super sports agent Jerry Maguire would also have struggled in Peet van Zyl's shoes: the fictional movie character did a lot for his clients, but at least he never had to testify in a murder trial involving his number one client.

The title character in the 1996 Oscar-nominated movie, played by Tom Cruise, has become the poster boy for sports agents - managing testosterone-filled athletes in their prime and juggling between keeping them focused on their careers and guiding them on the straight and narrow. Judging by his performance in the witness box this week, however, Van Zyl should perhaps have paid closer attention to one of the film's memorable one-liners, delivered by Maguire's mentor, Dicky Fox: "The key to this business is personal relationships."

Van Zyl has been Oscar Pistorius's agent for eight years. In that time, the two spent months in each other's company. He was one of the first people called on the fateful morning of Valentine's Day last year. This week, he took the stand to testify in the Blade Runner's defence.

But after prosecutor Gerrie Nel's brutal cross-examination, Van Zyl would have asked himself whether he had taken enough interest in his client's personal life, as Fox wisely reminded his protégé in the film.

Van Zyl, at first gently guided by defence advocate Barry Roux, painted a picture of a determined athlete who showed signs of paranoia because of crime and developed a heightened sense of vigilance.

He recalled walking with Pistorius in New York when a loud bang went off. "He grabbed me by the arm and looked scared ... I thought it was a strange reaction."

According to his version, he saw Pistorius "really" lose his cool only twice - on both occasions when media hacks peppered him with questions he deemed inappropriate.

He revealed why Pistorius wanted to take Reeva Steenkamp on an international trip with him, saying he "wanted to show her his world ... the amount of stress he is under and perhaps she will better understand [his life]".

Nel latched on to this later, saying it was all about "what he wants".

Van Zyl said Steenkamp was the first of Pistorius's girlfriends he wanted to take on an athletics trip, but Nel produced e-mails showing the athlete also wanted former girlfriend Samantha Taylor to accompany him in 2012. Van Zyl claimed he could not remember that exchange.

He also said he never tried to get to the bottom of why fellow athlete Arnu Fourie did not want to share a room with Pistorius at the 2012 Paralympic Games.

It was reported Fourie asked to be moved because he could no longer handle Pistorius's angry outbursts on the telephone.