Is It Ever Better To Be Unseeded?

As draw-probability takes go, this one is pretty spicy:

Satisfyingly counterintuitive if true. Is it?

A few reasons for skepticism: As an unseeded player, you could get a top-eight seeded opponent in the first round. Or the second. Or, after upsetting a lower seed–you are almost guaranteed to get one in the first or second round–you could still end up with a top-eight seed in the third round. Going into the draw unseeded is hardly protection against a top-eight opponent.

I could theorize further, but why not just delve into the numbers?

The men’s draw

Let’s look at a few examples from the draw. The 25th seed is Nicolas Jarry, who was drawn to face Carlos Alcaraz in the third round (ouch!). His grass-court Elo (gElo)–the number I use to generate forecasts–is 1698.5. The closest unseeded player to him on the gElo list is Adrian Mannarino, who has a rating of 1700.8. In Elo terms, a difference of 2.3 points is basically just a rounding error.

If Ricky’s theory is correct, on the morning of the draw, it was better to be Mannarino than Jarry. Except–oops!–Mannarino was drawn to face third-seed Daniil Medvedev in the second round.

How does all that good and bad luck shake out in the forecast? Jarry has a 7.5% chance of reaching the round of 16, 2.6% for the quarters, and 1.0% for the semis. Mannarino has 6.3% for R16, 3.2% for the quarters, and 1.1% for the semis. Those are awfully close, just like the near-identical gElo ratings would imply. The luck mostly washed out.

(If you look at my forecast after the tournament begins, the numbers will no longer be the same. That’s partly because every result has an effect on many other probabilities, and partly because the gElo ratings will slightly change when I add this week’s results from Eastbourne and Mallorca, which are not yet in the system.)

What about 26th seed Denis Shapovalov? Shapo has a gElo of 1675.1, roughly equal to unseeded Ugo Humbert’s 1676.1. Would it be better to be Ugo?

Shapovalov got lucky: His top-eight counterpart in the draw is Casper Ruud, a not-grass specialist who is barely rated higher than the Canadian. Shapo’s odds of going further than Ruud into the round of 16 are 25.3%. He has a 10.5% chance of making the quarters and a 3.4% shot at the semis.

Humbert was not so lucky. Like Jarry, he’s in Alcaraz’s section. He has a mere 3.5% shot at the fourth round, 1.1% for the quarters, and 0.4% for the finals. The way the cookie crumbled on draw day, it was much better to be Shapo than Ugo.

One more. Dan Evans is the 27th seed, with a gElo of 1693.1. The closest unseeded player in the draw is Sebastian Ofner, gElo-rated 1688.5. Evans lines up for a third-rounder with 8th-seed Jannik Sinner, who is much better than Ruud despite the number next to his name. Despite a tricky first-rounder with Quentin Halys and Sinner looming in the third, Evans’s chances of making the fourth round are 14.5%, along with 6.8% for the quarters and 3.2% for the semis.

By unseeded standards, Ofner got lucky. He drew almost-seeded Jiri Lehecka to open, but the seeds in his section are #18 Francisco Cerundolo and #16 Tommy Paul. With the benefit of that good fortune, his chances of lasting to the second week are 16.0%, with a 4.1% shot at the quarters and a 1.3% chance of a semi-final berth. By the numbers, I’d take Evans’s position over Ofner’s, though it’s pretty close.

So: three anecdotal comparisons, one saying it is definitely better to be the seed, one saying it’s marginally better, one saying it’s about even.

There’s one obvious counter-example. Tomas Martin Etcheverry, seeded 29th, landed in Novak Djokovic’s section. He has a mere 0.8% chance at the fourth round, 0.2% for the quarters, and everything else rounds down to zero. His own rating is part of the problem: He has little experience on grass.

The closest unseeded player in the draw to Etcheverry’s 1585.5 gElo is Daniel Altmaier at 1587.8. Altmaier ended up in the Sinner/Evans section, with an unseeded first-round opponent. His chances of reaching the fourth round are 4.8%, with a 1.5 chance of the quarter-finals.

So we can say one thing for sure: If you know you’ll be drawn to face Djokovic early, you might want to not do that.

The general solution

These are all anecdotes, and the forecasts are entirely dependent on this year’s actual Wimbledon draw. That doesn’t answer the question in any comprehensive way.

We can get closer to a general solution by running two simulations. First, forecast the 2023 Wimbledon field, with the actual seeds, without considering how the draw actually played out. So Etcheverry might have landed in Ruud’s section, or Mannarino might have drawn Djokovic in the first round.

Next, forecast the 2023 Wimbledon field, but instead of keeping the actual seeds, assign the 25th to 32nd seeds to the next eight players in the rankings. Instead of the 25th seed belonging to Jarry, we give it to Lehecka, and Jarry is unseeded, and so on.

By keeping the players constant and varying the seeds, we can see the effect of the seedings on 16 players: the actual seeds 25-32, and the “next eight” who just missed.

Here are the chances of those 16 men reaching the fourth round in the two scenarios, seeded and unseeded:

Player                       R16 Seed  R16 Un  
Nicolas Jarry                   15.3%   13.1%  
Denis Shapovalov                12.8%   11.0%  
Daniel Evans                    15.0%   12.8%  
Tallon Griekspoor               30.5%   28.1%  
Tomas Martin Etcheverry          6.1%    4.9%  
Nick Kyrgios                    20.6%   18.3%  
Alejandro Davidovich Fokina     12.8%   11.0%  
Ben Shelton                      4.4%    3.5%  
Jiri Lehecka                     9.7%    8.0%  
Matteo Berrettini               33.5%   30.9%  
Ugo Humbert                     13.2%   11.4%  
Andy Murray                     31.9%   29.4%  
Lorenzo Sonego                  19.8%   17.5%  
Miomir Kecmanovic                8.1%    6.5%  
Botic van de Zandschulp         14.0%   11.9%  
Adrian Mannarino                15.7%   13.6%

On average, these players have a 16.5% chance of lasting to the second week if they have a seed, 14.5% otherwise.

The same thing holds if we care more about other achievements, like reaching the third round, the quarter-finals, or the semis:

            R32    R16    QF    SF  
Seeded    40.5%  16.5%  8.4%  3.8%  
Unseeded  28.7%  14.5%  6.9%  3.1%

It’s better to be seeded.

Going wide

This isn’t a truly general solution, because it is based solely on the 2023 Wimbledon men’s field. You might think of this group of players as top-heavy, which would make it more valuable to avoid the top seeds. But while Djokovic and Alcaraz are well ahead of the pack, the top eight as a whole is not overwhelming dominant–just think of Ruud on grass.

We could construct a variety of other draws with different mixes of ability levels. You could imagine a field in which the top eight players were all outstanding and the rest were not. An extreme example like that might change the results. We’ll save that for another day. In the meantime, players: Keep chasing those seeds.

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