Justin Marshall: Springboks halfback Joost van der Westhuizen an inspiration to the end

Joost van der Westhuizen, a Springboks halfback I am proud to say I played against and became a friend of, has gone.

It was always inevitable when he was diagnosed with motor neuron disease, that's the reality of it. Unfortunately, alongside it being terminal, it's an aggressive disease.

It was predicted he would be lucky to see two years after he was diagnosed six years ago. He defied the odds with the fighting spirit we saw so often from him in the South Africa No9 jersey. He did everything he could to find a cure or at least prolong his life because he wanted to spend time with his two young children. He also did a lot of work with his J9 Foundation trying to help others.

It's happened, thankfully a lot later than was predicted but it doesn't make it better. The rugby world has lost another legend too young, too early. He was 45.

Joost will be forever linked with Jonah Lomu, our great All Black who was taken too soon. Joost came to the fore before the 1995 Rugby World Cup, which the Boks won. He smashed records and statistics. The feats he accomplished were mind-boggling. He scored 38 tries in 89 tests, both national records when he retired in 2003.

He was a competitor who played his heart out for the Boks as Jonah did with the All Blacks. Because of that he was a celebrity in South Africa, like Jonah was in New Zealand.

On his day Joost was the best halfback in the world and possibly the best player on the planet. How many times did we see Joost turn a game around? He could do something brilliant to change everything.

He was physical - he looked after Jonah defensively in 1995, and it wasn't just one tackle, there were many. He was strong enough to cut down Jonah in his prime. His 2m height made him imposing and he was very competitive with a unique understanding of the game.

I remember playing against him in the test in Pretoria in 1996, which we hung on to win and with it the series, the first time the All Blacks won a series in South Africa.

Joost sniped, fed his forwards, offloaded, took tackles. That was him in his element. The Boks didn't win but they kept coming and he was a big part of that.

He will be remembered for what he did on the field, but I remember him equally for how he went about approaching this disease. He was always positive and tried everything to beat it, but he also gave back.

I visited Joost in South Africa a few times. The last time was in May 2015 and that was the hardest. He was struggling to speak and hold his head up but still had a smile on his face. George Gregan and I had a couple of brandies with him. Joost still had a glint in his eye.

Joost could have dealt with this terrible disease as a recluse, and I wonder whether that's something I would have done. But seeing the way he approached it was inspirational.