Wayde van Niekerk won gold and silver medals at the world championships in London in 2017. Photo: Andy Rain/EPA

Olympic 400 metres champion Wayde van Niekerk is unsure whether he will defend his title at the World Athletics Championships in Doha in September, instead setting his sights on retaining the gold medal he won in Rio de Janeiro in 2016.

Van Niekerk, also the 400m world record holder, has been sidelined for almost 18 months after a serious knee injury sustained in a charity touch rugby game in October 2017.

It has been a slow road to recovery for the South African, who recently returned to the track for the first time to claim the provincial Free State championships title in a time of 47.28, some 4.25 slower than his best 400m mark.

“It would be nice to be in Doha later in the year, but I can’t tell just yet if I will be there for sure.

“My main target is the Olympic Games in (Tokyo) Japan next year, and I will be working as hard as I can to make sure I’m in good shape for that,” Van Niekerk said on Thursday.

“It is something that excites me, but I still have a lot of physical work to do.

“Mentally I feel very strong, but I just need to be patient and allow the physical side to catch up.

“I don’t know when it (knee) will be 100 percent, but my mind is set on doing what I can do‚ doing whatever is expected of me and seeing where that takes me.”

The 26-year-old concedes he battled in the first 200m of his return to competition, but felt more fluid in the second half of the race.

“My first 200 was extremely rusty. I was just trying to find my feet and my momentum again, but once I got that, it gave me the confidence that I can stay in it for an entire 400 metres.

“It has sparked more motivation, and also identified some key areas to be worked on. No athlete is ever pain-free – I just have one I caused myself. I must just take the knocks and carry on.”