Curling may finally be having its Moneyball moment

In a sport where millimetres can separate great teams from the merely good, elite curlers are turning to analytics more than ever to gain an advantage. It seems curling may finally be having its Moneyball moment.

Analytics are sweeping the game as more teams look for an edge

Olympic champion Anna Hasselborg of Sweden is one of the skips who has embraced analytics and seen it pay big dividends. (Greg Baker/AFP/Getty Images)

In a sport where millimetres can separate great teams from the merely good, elite curlers are turning to analytics more than ever to gain an advantage.

It's a phenomenon that's sweeping the game. That's right — curling may finally be having its Moneyball moment.

Inspired by the famous 2003 Michael Lewis book chronicling Oakland A's executive Billy Beane's revolutionary methods for building a baseball team, Gerry Geurts has spent years tracking thousands of rocks sliding up and down pebbled sheets of ice. The founder of the website CurlingZone saw the potential for using statistics to help better understand this old-school sport once synonymous with corn brooms and cigarettes.

"I saw Moneyball as an awakening in how to look at the game," Geurts says. "I was just getting involved in curling at the time, building a live scoring system for the Ontario Curling Tour. Then I did the same for the World Curling Tour. I saw an opportunity to collect a wide array of information that could be analyzed."

Essentially, what Geurts understood is that if curling teams knew how their opponents were likely to act in any given situation of a game, they would be better able to prepare and strategize. 

Today he has a database with results from about 175,000 contests. If there's an elite-level curling game happening anywhere in the world, it's likely that Geurts is tracking it. 

Using that data, he can challenge old assumptions. For example, what's the likelihood of a team winning a game if they go into the final end leading by one point without the hammer, as opposed to trailing by one with the hammer?

"It was a long-held belief that being down one with hammer in the last end was the preferred position to the opposite," Geurts says. "But with the numbers, we were able to show that [those] teams were only winning about 40 per cent of the time."

So why did many curlers believe the reverse for so long?

"It's all about being in control of the situation," Geurts figures. "No team enjoys standing on the backboards watching their opponent throw a potential game-winning shot, and having that hammer stone in their hands would prevent that."

Buying in

It's been somewhat of a long journey for Geurts, trying to get teams to buy into the numbers. Sure, the thinking goes, analytics are helpful, but at the end of the day curlers still have to make shots. But knowing the numbers can help teams decide on the right shot to try in any scenario. And that knowledge, Geurts says, is difficult to gain by simply playing the games.

"Teams would never play enough of any one situation in a season to get a proper sample size to understand the numbers," he says.

Top curlers have started to come around, and it's paying off. Take Sweden's Anna Hasselborg, the 2018 Olympic women's champion.
Gerry Geurts thinks curling has only scratched the surface of what analytics can do for the game. (Photo courtesy Gerry Geurts)

Before contacting Geurts two years ago, Hasselborg and her team had tried everything to break into the game's elite. They were gliding in mediocrity, ranked 22nd in the world. They needed a change and turned to analytics for an edge.

"I looked to other sports and poker and saw how much the statistical information was used," Hasselborg says. "I thought it was strange that in a sport like curling, where we constantly use odds and risk-and-reward judgements, that we didn't use this type of statistical information about your team and also your opponent's game."

Geurts spent the last couple of years pouring over the numbers with Hasselborg in the lead-up to the Olympics. Her rink arrived in Pyeongchang armed with an arsenal of analytics on every other team, allowing them to adapt their style of play as needed. Suddenly, a team that was virtually unknown a short time ago found itself playing in the Olympic gold-medal game.

"Very few people could have seen this team as a gold-medal contender as little as 18 months ago," Geurts says. "[But] they had so much potential and so much talent, and the minds to quickly rise through the ranks in the women's field."

And when it came to the biggest game of their lives, they dug even deeper into the numbers. Hasselborg had information on every aspect of South Korea's game. Sweden planned, executed and dominated, winning 8-3 to become Olympic champions.

Playing the numbers

Hasselborg isn't the only skip enjoying success with help from analytics. 

This past weekend in Toronto, Jamie Sinclair became the first American skip to win a Grand Slam of Curling title by defeating Canada's Jennifer Jones.

Jones came into the final riding a 27-game winning streak after capturing her sixth Scotties Tournament of Hearts title and then going undefeated to claim her second world championship.

American skip Jamie Sinclair, who upset Jennifer Jones to win the Players' Championship, is another believer in analytics. (Paul Chiasson/The Canadian Press)

Sinclair, who was making her first appearance in a Slam final, credits the analytics for helping her avoid feeling overwhelmed by the matchup and ultimately pull off the 7-2 upset. 

"Seeing the numbers and getting a good idea of how the team plays takes the players out of the picture and I'm just playing against the numbers," she says. "There's less intimidation.

"It felt like we were in control. We were definitely predicting how the ends were going to play out."

Fellow American John Shuster has also turned to the numbers, helping him become the first U.S. skip to win Olympic gold, which he did in Pyeongchang.

Geurts says teams are becoming believers because the numbers don't lie. And this is just the beginning.

"The work we've done so far still feels very rudimentary and basic," he says. "But we also understand human nature and what it takes for teams to do things differently. It's a whole new world as curling grows up, joining many other major sports in embracing evidence-based decision making.

"We've just scratched the surface of what is possible in this game."


Devin Heroux

CBC reporter

Devin Heroux reports for CBC News and Sports. He is now based in Toronto, after working first for the CBC in Calgary and Saskatoon.