Even after a visibly shaken Chinese tennis star Zhang Shuai retired from a match against Hungarian Amarissa Kiara Toth in the Hungarian Grand Prix on Tuesday, a video clip of their contest is making waves on social networking sites.

What triggered the interest was Zhang's protest to the judge after a forehand she hit appeared to hit the line, but was ruled outside the line. Even the chair umpire took a look and ruled the ball was out.

Zhang was not happy with the verdict and asked to speak to a tournament supervisor, but despite her protests Toth walked up to the ball mark and erased it with her shoes.

Many media outlets and tennis players have retweeted the video since, saying the ball fell within the line. It is not for us to decide if the ball did or didn't fall within the line, but Toth removing the mark before the dispute was settled was certainly not a good deed.

It is akin to civil cases in which if one side destroys evidence then it makes the case of the opponent stronger. It is not surprising Zhang asked the judge why Toth had removed the mark if the ball, indeed, fell outside the line.

The judge on site did nothing to record where the ball fell or stop Toth from removing the ball's mark. Although Toth emerged victorious, a victory derived in this manner is certainly not worth celebrating.

Sports is purely mankind's challenge to better itself and the competition should be as fair as possible. Race, color, nation or any other factor should be totally irrelevant in such competitions. There should be no room for doubt or bias. Those are enough grounds to suggest that Zhang should not have been treated in this manner.