'Why didn't Kane Williamson walk?'

June 20 (CRICKETNMORE) Former South Africa spinner Paul Adams has questioned the ethics of New Zealand skipper Kane Williamson after his team defeated Faf du Plessis' men in a thrilling World Cup encounter.

On Wednesday, Williamson played a captain's knock and showed nerves of steel as he remained not out at 106 to make sure the Black Caps chase down the 242-run target against South Africa without much hiccups. His innings was decorated with nine fours and a six, as the Kiwis saw off stiff resistance from the Proteas to win the nervy battle with three balls to spare.

However, his innings was marred by a controversy after he was caught-behind by Proteas wicket-keeper Quinton de Kock in the 38th over of the inning bowled by leg-spinner Imran Tahir. But, the Proteas did not request a review, only for replays to show a nick.

"Why didn't Kane Williamson walk," tweeted Adams, thus sparking a debate on the micro-blogging website. "If Kane Williamson was Mankad after he didn't walk. Would he be upset," he said in another tweet.

Meanwhile, du Plessis, in the post-match presser, explained that he trusted de Kock's judgement and that's why he didn't go for a review. 

"We weren't aware of it. I think I was at long on at the time, and Quinny is the closest to the action. He's always my go to man," du Plessis said, when asked about the reprieve. 

"I just thought it was a plain miss. I just heard about it now at the post match that he said he had a nick on it. But even Kane said he didn't know he had to fine tune it. He would have referred it. But that's not where the game was won and lost," he added.

With just three points from six games, the Proteas are all but out of the contention for the semi-finals.