The stat that proves Emma Raducanu is world-class, and has a shot at Iga Swiatek

MELBOURNE — Emma Raducanu could hardly have wished for a bigger challenge in the third round of the Australian Open, but to be the best you have to beat the rest. And there aren’t many better than Iga Swiatek.

As an unseeded player, Raducanu cannot expect to avoid the top players until the later rounds, and the run to the US Open title she enjoyed – only playing two top-20 players and none from the top 10 – was almost without precedent.

But according to one statistical analysis, Raducanu has no reason to fear clashes with top players, and in fact is a good enough player to be seeded, if she can just become consistent enough: the Elo rankings show she is in fact the 13^th-best player in the world right now.

What is Elo?

Designed by Hungarian-American physics professor Arpad Elo, the Elo ratings was created to allow chess players to match up against other players of a similar skill level. A higher rating indicates a better player, and players can improve their rating by beating other players of higher or equivalent rating.

Jeff Sackmann, who runs the statistics encyclopaedia Tennis Abstract, wanted to adapt the system for tennis, to create a more accurate picture of the tennis world than the official rankings could.

“It is more accurate in the sense that the two systems do different things,” Sackmann tells The i Paper.

“So the official rankings measure how well you have played based on the tournaments you played in and the rounds you reached: so round of 16 at a major is round of 16 in a major, whether you beat Carlos Alcaraz or whether you beat Jaime Faria [the qualifier ranked 125 in the world whom Djokovic beat in Australia this week].

“So [in order to rise up the rankings] you want to play a lot, you want to win a lot of matches. It doesn’t matter who you play.”

This does not suit Raducanu, who has been blighted by injury but played high-level tennis when fit, even if her crowning achievement was rated better by the official rankings than by Elo: Raducanu’s US Open title, while still a remarkable achievement, does not carry the same weight as, for example, Rafael Nadal’s 2013 French Open title, when he beat three top-10 seeds in a row including Novak Djokovic, to win it.

What do the players think?

Swiatek agrees that the official system is not necessarily worth using to assess opponents.

“Honestly there’s no point to look at rankings, especially when you have these great players that already have been through great tournaments and won some tournaments. You know that they can play well,” Swiatek said.

“Maybe they’re not consistent to have the ranking, but still, you need to be on your toes and ready because you don’t know what they’ll show this week.”

Perhaps if Swiatek studied the Elo ratings, she might spend a little more time looking at the rankings.

Sackmann adds: “Elo is different in the sense that tournament doesn’t matter and round doesn’t matter, the only thing that Elo looks at is who you play and whether you win.

“So if you beat Jaime Faria in round two of the Australian Open, you get exactly the same value out of that as you get from beating Faria in the first round of a Challenger.

“What Elo does is it tells you how well everyone’s playing. Period.

“It’s not a measure of fairness. It’s not a measure of who’s been playing the best for a year. It’s not a measure of who should get into tournaments. It’s a measure of who is playing better right now, and basically, how should we expect them to play their next time on court.

“If you’re going to make bets on today’s matches, you’re going to do better using Elo, than you’re going to do using the ranking system. And that’s pretty extensively tested.

“The official ranking systems are basically an average of how you’ve played over the last 12 months, so it’s really a measure of how good you were six months ago, and even then, it’s imperfect because it doesn’t take opposition into account.”

What does it mean for Raducanu?

No woman, except for the recently returned new mother Belinda Bencic, is more under-ranked by the official rankings, according to Elo.

And you can use the Elo ratings that Sackmann has designed, which is virtually the same as the chess algorithm but with penalties introduced for absences and injuries and separate rankings for each surface, to predict the outcome of matches.

If you look at the world rankings, which have Raducanu at No 61 and Swiatek No 2, you would expect this to be a straightforward result. But with Raducanu up to No 13 in the overall rankings and 19 in the hard-court ones, you might think the match would be a little closer.

However, such is the gulf in class between the very best hard-court players in the women’s game at present and the rest, Raducanu is still a significant underdog.

Using the difference in their ratings (just over 250 points) and Sackmann’s formula, we find that Raducanu has just an 18.9 per cent chance of victory. The bookmakers give her even less chance.

”I think the last two rounds have been amazing preparation,” Raducanu said. ”I’ve played two really top opponents. Amanda [Anisimova, whom Raducanu beat in the second round] is also someone who is unseeded but someone who’s taken out some of the top players in the game and is extremely dangerous.”

Anisimova, incidentally, is ranked No 18 and one place higher than Raducanu in hard-court Elo.

Raducanu added: “So I have to take a lot of confidence from that and I do. I’m going to enjoy going out there and playing Iga. She was No 1 for so long and getting to play on a big court will be really fun as well with the atmosphere here, which has been great so far.”