With tears streaming down his face, Bert blurted out “Unbelievable” several times, and one of his most memorable lines was “Just look at him, he’s such a beautiful boy!”.

On Monday night (Tuesday morning SA time), Chad le Clos took a surprise silver medal in the 200m freestyle, his first of the Games, behind China's Sun Yang.

Le Clos' medal was Team SA's second after Cameron van der Burgh also took silver in the 100m breaststroke.

Le Clos will be back in the pool for the final of the 200m butterfly (03:28 SA time) on Wednesday morning where he will come face-to-face with American legend Phelps who he famously edged to take gold in London four years ago.

Recent times have been tough in the Le Clos household as both Bert and his wife Geraldine have been fighting cancer.

Geraldine, has had her breast cancer return, while Bert has developed prostate cancer.

Geraldine has undergone a double mastectomy, while Bert has lost 30kg in weight in the past six months.