Stats: The Ruthless Efficiency of Serena Williams

Last night Serena Williams obliterated World Number 4 Agnieszka Radwanska 6-0, 6-3 in the semifinals of the Miami Premier Mandatory. The fourth best player offered such little resistance to one of the all-time greats of women’s tennis that it even felt like the final score could’ve been even more lopsided.

Before the match started, I decided to track Serena’s forehands and backhands, just to get a glimpse at what her Efficiency Ratings were on both wings. As you might recall, I did the same thing for Maria Sharapova during her quartefinal match against Sara Errani. Just as a reference, here is how the Forehand and Backhand Efficiency Ratings are calculated:

Forehand Efficiency rating = (Total Attempted Forehands – Forehand Unforced Errors)/Total Attempted Forehands

Backhand Efficiency Rating: (Total Attempted Backhands – Backhand Unforced Errors)/Total Attempted Backhands

As the match started, Radwanska seemed to be more nervous than usual. The top Polish tennis player was struggling to get first serves in play (midway through the first set her first serve percentage was below 40%). Serena Williams, on the other hand, was fully focused on the task at hand: she played one of the most controlled and efficient sets of tennis I’ve seen in recent times. The result was a most emphatic bagel.

Here is my first set scorecard:

Per usual, the blue highlight on games 2, 4 and 6 indicate that Serena broke Radwanska’s serve in those games. Here are a few interesting things about that set:

– Notice that the 15-time Slam champion didn’t have to hit more than 9 groundstrokes in any of those six games, which is astounding (remember, first serve returns don’t count as groundstrokes in this analysis).

– It’s also interesting that Serena hit seven more backhands than forehands throughout the set.

Here are the Unforced Errors (via TennisTV) and Efficiency Ratings for the younger Williams sister:

As you might recall, Serena’s Efficiency Ratings closely resemble what Maria Sharapova achieved during the first set against Errani the other day (Sharapova had an 86% Forehand Efficiency Rating and a 94% Backhand Efficiency Rating). However, Sharapova had to hit 71 more forehands and 53 more backhands to get those numbers…and she had to scrape through a hard-fought 7-5 set.

Isn’t it shocking how efficient Serena Williams is? Here’s another clue:

 As you can see, Serena Williams had to hit only 25 groundstrokes to hold serve three times. That’s an average of a little over 8 groundstrokes per game. And since you have to win at least four points to win a game, we can say that Serena had to hit only about 2 groundstrokes per point during her service games during that set.

That is just astounding.

While I was collecting this information, I couldn’t help but wonder at how incredible Serena Williams’ serve is. It’s about five or six steps above everyone else on the WTA. Not only does she rack up the aces, but she gets a good number of service winners in. And if the returner somehow gets the serve back in play, Serena more often than not has great looks at relatively simple putaways. It’s the complete package.

Just look at the stats from that first set:

That’s just brutal. 2 out of 3 serves in that set were first serves, and Serena won 82% of the points played with her first delivery. She added 4 aces and didn’t commit a single double fault.

Really, tennis efficiency doesn’t get any better than that. And what is scary is that Serena wasn’t even pushing that hard: she was just picking her spots with clinical precision, and not going for more than she needed to. Winning that set seemed like the easiest thing in the world. Everything about it made perfect sense.

Now, what happened in the second set? Let’s check the scorecard:

A few things things stand out:

– Serena went from hitting 7 more backhands than forehands in the first set to hitting 22 more forehands than backhands in the second set. That’s pretty significant, no? You can see a tactical adjustment from Radwanska, who knows that even though Serena’s forehand is a fierce weapon, the World Number One was more likely to make errors off that wing than off her incredibly solid backhand.

– You can also see that in the second game of the set (a Radwanska service hold), this trend of making Serena hit significantly more forehands than backhands resulted in the first game won by the former Ninja of the WTA. It also resulted in Serena having to hit one fewer groundstroke than in all of her first set service games combined (24 to 25) and coming out of the game empty-handed. .

– Look at the sixth game, when Serena Williams finally got the break she was looking for: she did it with only 3 groundstrokes (again, first serve returns don’t count as groundstrokes). I actually went back and looked at this game again, just to double-check the numbers. That’s another aspect of Serena’s efficiency: her impressive return game.

You can see it in action during matches: Serena Williams will be looking to do heavy damage off of most of her returns of serve. She loves to hit returns into the open court, as well as with a wicked angle. She is  always looking to inject a lot of pace – sometimes hitting a return at a higher speed than the serve itself. What is fascinating is that the whole process doesn’t seem reckless. Such is Serena Williams’ control off both wings.

– You can see that even though Serena played one more return game in the second set than she did in the first (and also played that long 2nd return game), she ended up hitting just 5 more groundstrokes on her second set return games than in her first set return games. So even if she didn’t end up breaking Radwanska’s serve more than once, Serena didn’t spend all that much energy in those return games anyway.

Now, how did the serve fare in the second set? Serena added 8 more aces, and just a single double fault (in the last game of the match, too). Her first serve percentage dipped slightly, but she increased her percentage of points won with it (to 84%). She also increased her percentage of points won with her second serve, from 50% in the first set to 60% in the second.

So, her serving efficiency actually went up. Why did this set become more of a contest? Let’s look at the unforced error count, as well as the Efficiency Ratings:

As you can see, Serena Williams committed far more forehand unforced errors in that second set (she only committed 4 in the first set), while she actually had fewer backhand unforced errors. However, as I mentioned above, Serena hit significantly more forehands than backhands in that second set (22 more). Hence, her Forehand Efficiency Rating went down.

Here you can see an interesting pattern during the first five games of the second set:

You can see that in the first five games (which included 3 Serena service games and 2 return games), Venus’ younger sister hit a combined 21 more forehands than backhands. She had to work harder to hold, and even though she put a lot of work into at least one of those return games, she didn’t break serve. It’s interesting to note that in the next four games combined, the differential between forehands and backhands would just be +1 in favor of the forehand.

Now let’s step back a little and look at the final match stats:

Let’s add the following numbers to Serena’s final tally: 12 aces, just 1 double-fault, 64% of first serves in, 83% of first serve points won. Serena hit 15 forehand winners, and 11 backhand winners. Her total number of winners, 40 (which includes aces and overheads, the latter of which I don’t tally as groundstrokes), is greater than the number of points won by Radwanska throughout the match (37).

As a quick comparison, let’s go back to that Sharapova-Errani match. The Russian had to hit 189 groundstrokes to win the first set, as well as 164 to win the second set.

Last night, Serena Williams only had to hit just 157 groundstrokes to win the entire match.

If that’s not efficiency, I don’t know what is.