Surprise Semifinalists at the Australian Open

Of the eight singles semifinalists in Melbourne, only two entered the tournament seeded in the top four. Rafael Nadal, the top seed in the men’s draw, has survived, and Li Na, the fourth seed in the women’s draw, is the highest-ranked player still alive on her side.

We haven’t exactly followed the script.

The women’s singles draw, with the top three seeds eliminated, is particularly unusual. It is only the 10th time in the last 35 years that none of the top three seeds have made it through to the final four of a Grand Slam. Such events have been heavily concentrated in the last decade or so–the fourth seed was the highest-ranked surviving player at Wimbledon in 2011 (Victoria Azarenka) and 2013 (Agnieszka Radwanska), and the fifth seed was the apparent favorite at Roland Garros in 2011 (Francesca Schiavone).

You might notice a pattern. In these nine Slams when no top-three seed reached the semifinal stage, the best remaining player didn’t fare so well. Both Vika and Aga fell to lower-ranked opponents when they were the remaining favorites at Wimbledon, and Schiavone lost her shot at the French Open to Li. Only twice in these nine majors did the highest-remaining seed in the semifinals go on to win: Martina Hingis, when she was seed fourth at the 1997 Australian Open, and Anastasia Myskina, when she was the sixth seed at the 2004 French Open.

In a tournament full of surprises, we might not be done yet. It stands to reason that once the favorites are eliminated, the odds of subsequent upsets increase. The lower you go in the rankings, the less difference there usually is between players–there’s a bigger gap between Azarenka and Maria Sharapova than there is between, say, Jelena Jankovic and Angelique Kerber. The smaller the gap, the more likely the upset.

While only one top-four seed remains in the men’s draw, the odds of upsets are moving in the opposite direction. While Nadal can always count on a tough fight from second-seed Novak Djokovic, he typically has little trouble with lower-ranked players. He has won his last 15 matches against the other three players left in the drawRoger Federer, Tomas Berdych, and Stanislas Wawrinka–and lost only 4 of 41 matches against the trio since 2008.

The historical precedent for this sort of semifinal draw also favors Rafa. 14 Grand Slams in the Open Era have featured a semifinal round in which the top seed is the only one remaining of the top four. The top seed has gone on to win 9 of the 14, including 8 of the last 10. The most recent final four that fit this profile was in Melbourne four years ago, when Federer swept the final two rounds without losing a set.

But even this rosy picture for Nadal offers Roger a glimmer of hope.  The last time the top seed was alone in the final four and didn’t go on to win was the 2002 US Open. Lleyton Hewitt was the #1 who failed, paving the way for a 31-year-old Pete Sampras to win one final slam before he retired.

Roger isn’t going to call it quits this week, but he’d sure like to emulate Pete’s success in seizing a wide-open Grand Slam draw.

A Quarterfinal on Federer’s Racquet

The Roger FedererAndy Murray head-to-head is a bit of a baffling one. In twenty career meetings–18 of them on hard courts–Murray has won 11, including four of the last five.

Yet for a superficially tight one-on-one record, Fed and Murray haven’t played many tight matches against each other, especially lately. When they went five sets in last year’s Australian Open semifinal, it was the first time they had gone the distance in ten matches. The outcome of a match between them is up for grabs, but whoever wins it tends to do so by a handy margin.

Even that five-set semifinal last year wasn’t as close as it looked. Murray won 54.0% of total points and racked up a Dominance Ratio (DR) of 1.32, meaning that he won far more return points than Roger did. Five setters are usually much closer to 50% and 1.0, respectively. While Murray won far more points, Federer displayed his historically-great tiebreak skill to keep himself in the match.

DR is a convenient measure of the closeness of a match, where 1.0 is a dead heat. Only two Fed-Murray matches–both before 2009–fell in the range between 0.85 and 1.15. By contrast, Novak Djokovic and Rafael Nadal have played seven matches (including two Grand Slam finals) in that range, and Djokovic and Murray have played five.

Tactical nonsense

To traffic in conventional wisdom for a moment, Federer is the most aggressive of the Big Four, while Murray is the most passive. To the extent Andy is likely to hurt Roger, it has more to do with his ability to force Fed into trying to do too much, particularly on the backhand side. If Federer plays patiently and picks his spots, he can crush Murray. If he plays too passively or hits bunches of unforced errors, it can be a rough day at the office.

However, there may not be much Murray can do to determine which Roger shows up.  Simply forcing Fed to hit backhands certainly isn’t enough. The Match Charting Project has amassed shot-by-shot data, including the number of groundstrokes hit from either side, for 23 Federer matches so far. Nadal is particularly good at directing the ball to Federer’s backhand, forcing Roger to hit 56% to 58% of groundstrokes from the backhand side in both a win (last year’s World Tour Finals) and a bad loss (the 2011 Tour Finals).

Taking the average of these 23 matches (most of which are Federer wins, as the Match Charting Project seems to have drawn lots of Fed fans), Roger hits 52.5% of his groundstrokes from the forehand side. This reflects the balance of two factors: Federer wanting to hit his forehand, and opponents trying to keep the ball away from it.

Surprisingly, hitting lots of balls to Fed’s backhand side seems to have few benefits. There is no meaningful correlation between DR and the percentage of groundstrokes Fed hit on the backhand side.

Based on the limited data available, it appears that Murray has tried a variety of tactics.

In the two Fed-Murray matches for which we have shot-by-shot data–the 2010 Australian Open final and the 2012 Dubai final–Murray took opposite approaches to the problem. In the Melbourne final, he managed to direct 57% of balls to Fed’s backhand, which is as good as anyone but Nadal has managed. In the Dubai match, Roger hit 64% of his groundstrokes from the forehand side, the second-highest rate of any of the 23 Federer matches in the database.

In both cases, Murray lost. To take another example, Juan Martin del Potro has beaten Fed while letting him hit 57% forehands and lost to him while forcing him to hit 57% backhands.

The database–limited in matches and biased as it is toward Fed’s victories–probably can’t take us any farther. But from here, we can speculate that Federer has it in his power to win or lose regardless of the tactics thrown his way. Murray, like Nadal, has always forced him to hit one extra ball. The sort of aggression that takes a player far out of position to hit, for instance, an inside-out forehand can backfire against such a talented defensive player.

In four matches at the Australian Open so far, Federer has offered us plenty of glimpses of his glory days. Murray will likely prove to be his biggest test of the tournament, but Fed’s fate still hangs on his own racquet.