"People tend to forget about what he has done and focus on the unfortunate incident that happened," Mogawane said on Wednesday.
"He has done a lot for the country and for disabled people. He put many smiles on people's faces. He was able to put South Africa in the world spotlight. I definitely think that his contribution will stand the test of time. People will not forget."
Mogawane formed part of the team in the 4x400m relay at the 2012 London Olympic Games, where Pistorius became the first double-amputee to compete in both the able-bodied and Paralympic track events at the global showpiece.
In 2011, the pair were part of the 4x400m relay team -- with Willie de Beer and Shane Victor -- which set a new national record of 2:59.21 at the IAAF World Championships in Daegu, South Korea.
The 32-year-old Mogawane was a regular training partner of Pistorius, spending four years at the University of Pretoria's Athletics Stadium, where they competed under the banner of Athletics Gauteng North.
Mogawane said Pistorius's shooting of his girlfriend Reeva Steenkamp on Valentine's Day last year had overshadowed the legacy he had created in South African sports history.
"The first thing that comes to mind when thinking about Oscar is that he was the guy who killed his girlfriend, forgetting that he was the same person who [has] done so much for the pride of the nation."
The 400m specialist said he tried to console Pistorius when he bumped into him unexpectedly.
"I spoke with him last year in December when I ran into him at the gym. I tried to tell him that in life things happen. It's tough to talk with someone in that situation."
Mogawane said he had been divided on what to do throughout the trial in the High Court in Pretoria.
"On one side you feel like you should be there with him, supporting him, but at the same time one needs to give him space so that he can go through it all."
The celebrity which came with being a star athlete was difficult, as his every move was scrutinised, Mogawane said.
"One wrong move and you will get nailed for it, especially when you are in the public eye."
Mogawane said athletes were constantly under pressure to perform and the weight of expectation sometimes influenced emotions.
"When you are a sportsperson, it's different from when you are a normal person. As athletes we are tough on ourselves and sometimes we react differently to things.
"We have our own pressures that we have to deal with. If on a certain day training didn't go well, we can get hard on ourselves and people around us. You feel bad and can get angry for having a bad day on the track."
He said most people did not understand the challenges athletes faced when competing for the nation.
"When we participate overseas we are like troops who have been deployed in a foreign nation. We leave everything behind, our wives and kids, to represent the entire nation.
"We go out there to give our all for the honour and pride of the nation."