A Deeper Look: Serena Vs Kerber
Published October 22, 2013 12:12
Serena Williams takes your breath away.
Williams was in devastating form, defeating Angelique Kerber, 63 61, in their opening round match of the TEB BNP Paribas WTA Championships in Istanbul and looks well positioned to repeat as champion at the end of the week.
Consider the honesty of Kerber's post match comments. "Today she was playing unbelievable, and I had actually no chance," she said. "It's tough to play against Serena like this. I think I served good, but she was returning unbelievable. Actually, she didn't give me a small chance to breathe, and I had, in the whole match, I had actually the feeling that she gives me pressure all the time."
Hard to play tennis when you can't breathe.
Williams looked devastating from the stands, felt unbeatable from the other side of the court and is redefining what's possible with post-match statistics.
Hawkeye visualization and SAP analytics produce various graphs and reports to help explain what we see but Williams consistently creates reports that, well, only she can produce. Her domination can be seen with the eye but even more so with the rich data that's now streaming into the sport.
The first mind-bending piece of information is Hawkeye's heat map, which tracks player movement. Serena's is small and centered right in the middle of the court with a sizeable percentage inside the baseline. Most importantly it doesn't stretch outside the singles lines. Kerber's on the other hand stretches well outside the doubles line on both sides and is twice as big.
Hard to breathe when you run so much.
That has a direct result in court position where Williams once again dominated. She hit 62% of all rally balls behind the baseline and 38% inside the baseline. That's aggressive enough to draw blood in most matches and has a direct relationship in pushing the opponent back further where they can't hurt you. Kerber hit 81% of her rally shots behind the baseline and 19% inside it. Generally it does not matter exactly what the numbers are - only that they are better than the person standing on the other side of the court. Advantage, Williams.
Williams' obsession with standing up in the court starts with the return of serve, where most players are just happy to neutralize the serve and get into the point. For Williams it's a golden opportunity to win the point before it even starts. Kerber was only able to force Williams to have her return contact point fully behind the baseline on three first serves for the match. The rest were either on or well inside the baseline and second serve return contact points were further forward still. Kerber by comparison only hit nine total inside the baseline. It's so tough to beat Serena when she is all over your serve and you can't pounce on hers.
Both players were pretty equal with rally direction with Williams hitting 51% of her shots to Kerber's backhand and Kerber hitting 52% to Williams' backhand. The only problem was that Williams had the upper hand in ball speed, depth, direction and court position in the majority of those points.
Lastly is serve direction. The scatter graphs in the service boxes are very well defined for Williams and move haphazard for Kerber. Hitting your spots has always been a good thing to do in tennis. Williams looked good from all angles of the sport and while she is breathing easy with a great start to the event, the pulse just quickened a little for seven other players.
Craig O'Shannessy is an Australian tour coach who studies matches to uncover the patterns and percentages that dominate the game. He runs a tennis academy in Austin, Texas and a website called www.braingametennis.com.