Now You Can Bet On Single Tennis Matches At Kalshi
Weekly roundup: Coinbase, Robinhood CEOs talk prediction markets; more on the comments sent to the CFTC ahead of a roundtable discussion
The most interesting thing we’re tracking at The Event Horizon is the evolution of what sporting events you can bet on trade at Kalshi.
Kalshi has slowly grown the portfolio of sports markets since the start of 2025, but the biggest expansion happened this week.
Dozens of single professional tennis matches have been posted and traded at Kalshi in the past couple of days, perhaps its most aggressive foray into sports betting so far. For example, here are some of the now-resolved markets for the rounds of 32 and 16 at the WTA Mérida Open:
Trading has been pretty de minimis so far; trading on all pro matches appears to be around $100,000 this week.
When matches are going on, Kalshi also has live score tracking that appears to be as fast as the feeds the sportsbooks use. (There are no markets for single matches as I type this on Thursday morning, but a source at Kalshi told me those markets will likely spawn later.)
Kalshi had already dipped its toe into single-game betting for the NFL, when it offered markets for who would win the AFC and NFC championship games. Those were phrased as futures markets, but in reality they were moneyline bets on the outcome of the games. (The Super Bowl market started as a futures market that involved multiple teams. By the end, it had become the equivalent of a moneyline bet on the Kansas City Chiefs or the Philadelphia Eagles.)
It’s interesting to note that Kalshi has already self-certified betting on single games for team sports — allowing for the equivalent of moneyline betting on game outcomes — but it hasn’t deployed those markets yet. It’s not clear why they haven’t, given that they have YOLO’d their way into sports betting otherwise. The “who will advance” language construction in a tennis market seems to be tailored to avoid a “who will win the match” market.
It’s feasible that Kalshi has been asked behind the scenes to hold off. Earlier, the CFTC had asked for sports markets not to go live during a review period, and Robinhood quickly backtracked on a plan to offer sports markets.
In any event, Kalshi is now into single-game/-match betting in a more meaningful way. A few final notes:
Tennis is famously one of the sports that has the most integrity concerns when it comes to gambling. While the WTA- and ATP-level events (top tier of women’s and men’s tennis) are not usually of concern, the concerns are greater than zero. That’s especially true in a gambling platform without some of the same safeguards and monitoring protocols deployed at regulated sportsbooks.
I (and others) question the hedging and price discovery utility stemming from obscure tennis matches.
Sports market update
Here are the sports markets that Kalshi currently offers as of Thursday morning:
Basketball, 12: NBA and college; both overall and conference championship winners.
Soccer, 15: Various league champion markets, but also markets about which teams will advance to the Champions League quarterfinals (essentially head-to-head markets).
Tennis, 5: Champions of majors plus winner of ATP Dubai. Markets for single-match outcomes appear to be spawning in the app and site as the start times draw near.
Golf, 5: Five tournament winners, including a live market for the winner of the Cognizant Classic, currently in play.
Baseball, 3: Still just league and World Series winner markets. Kind of interesting how they are listing team names for cities with multiple ballclubs — Los Angeles D (currently at 25% to win the WS); New York Y (26% to win the AL Pennant).
Football, 2: College football champion and 2026 Super Bowl.
Formula 1, 1: Drivers Champion.
Hockey, 1: Only Stanley Cup winner after the 4 Nations winner market settled.
Notably, the 4 Nations market got over $1 million in volume, with most of it coming during the final game.
Also notably, the Kalshi market had the outcome mostly wrong, with the eventual winner (Canada) only being a favorite while they were ahead 1-0 in-game. Once the U.S. went up 2-1, the market was back to favoring the U.S. to win where it remained until Canada won in OT on a goal off the stick of NHL star Connor McDavid at the 8:18 mark.
Esports, 1: League of Legends World Champion which is trading live, with not a lot of volume.
More on comments on prediction markets to CFTC
The CFTC released letters submitted by 19 different entities on Wednesday weighing in on the future regulation of prediction markets ahead of an announced roundtable. (One was added later in the day from the original 18.) While many of the letters expressed disapproval of the offering of sports prediction markets – including those from a number of tribal gaming entities and regulated gaming stakeholders like the American Gaming Association and Rep. Dina Titus (D-Nevada) – there were some supporters.
Geocomply stands out as a key legal gaming stakeholder that offered a more balanced stance on the matter, even stating in their introduction: “We appreciate the CFTC's leadership in exploring these new market opportunities and fostering greater consumer choice.”
By their own definition (included in the letter), Geocomply is “a global leader in digital risk analysis and fraud prevention technologies, specializing in providing online sports betting, iGaming, financial technology, and digital asset platforms with accurate and reliable location intelligence.” Considering Geocomply’s stated association with fintech and digital asset platforms, prediction markets (of the sports variety or not) could represent an emerging business opportunity, especially if the platforms find themselves in need of enforcing any state-specific restrictions.
In fact, the letter heavily focuses on the need for market regulations to respect state-level rights and state-specific sports betting regulatory frameworks.
“We believe that sports event contracts represent an exciting area of innovation with the potential to offer consumers new and engaging ways to participate in the financial markets. However, we also recognize the importance of ensuring clarity in the eyes of consumers and also of course respecting the established regulatory frameworks in place for sports betting activities, particularly at the state level.
“Many states have carefully considered the regulation of sports betting, weighing the potential benefits against concerns about social impact and market integrity. These deliberations have resulted in diverse approaches, with some states embracing legalized sports betting while others have chosen not to. We believe that any federal approach to sports event contracts would ideally acknowledge that state-level prerogative.”
Geocomply also requested, for the sake of clarity for both consumers and federal and state regulators, for the CFTC to “establish a clear distinction between federally regulated financial products and state-regulated betting products,” adding:
“We suggest that it is in everyone's interest that event contracts, whether related to sports or other areas, that do not fall under the definition of gaming according to CEA section 5c(c)5(C), be clearly differentiated from legal gaming activities within states.”
The new submission that was posted since yesterday was a 322-page(!) document from a lawyer, Jeremy Weinstein. Here is one of the more interesting takeaways from his comments:
The availability of hedging instruments, including those traded in public futures markets, is an essential tool for businesses to mitigate commercial risks, and enhances a business’s ability to succeed. Football game futures contracts would give this tool for success to organized crime: illegal bookies could hedge their commercial risks by using the futures markets for layoff betting. That success would inflict on the public more of the harms that accompany illegal gambling, including money laundering, loan sharking, extortion, game-fixing, corruption, and broken families.
Recognize also the slippery slope. Analogizing to the stretch arguments of football futures proponents that such contracts have an economic purpose hedging ancillary football activities such as vendors at winning/losing team stadiums, a futures exchange could argue that a contract on illegal narcotics, such as the price of heroin, could help police departments hedge budgets, since high prices incentivize crime, more of which requires more police resources. But such contracts would allow heroin producers and distributors to be more successful by having available tools to hedge their commercial risk.
I would love to see a market posted at Kalshi about whether the CFTC will actually hold a prediction markets roundtable in DC. It feels like there’s a non-zero chance a roundtable doesn’t happen once the new CFTC chair takes the reins.
The Closing Bell
A roundup of prediction market industry news and thoughts:
Coinbase on prediction markets: CEO Brian Armstrong spoke about prediction markets on CNBC: “I am excited about prediction markets and I think that the new CFTC chair Brian Quintenz is certainly very thoughtful on this topic and he’s going to have to figure out how to create a trusted environment where these things can be built in the United States so Americans can use them, but also make sure that consumers are protected.”
“As an example, you’d want to make sure that you don’t have any sort of prediction market where someone might be incentivized to harm another person, right? Just sort of basic rules like that.
“But overall, I think that people are going to use prediction markets to figure out what’s actually happening in the world. I actually think of it … It’s less of a trading product and it’s more of like an alternative to the New York Times or something … But I think people are trying to figure out what’s happening in the world and they’re increasingly worried about misinformation and they want a source of truth. And prediction markets are emerging as an important source of truth where people have real skin in the game. And that’s an exciting development where crypto can help.”On the insider trading question: “There’s an interesting question for prediction markets of like, do you want to let insiders trade … You know, in the commodities world, it’s sometimes a different question than in the securities world, right? Like if something is truly decentralized, anybody could have information on it. It may be a different lens, but I’ll leave that to the regulators to think about. I haven’t formed my opinion on that fully yet.”
Robinhood on prediction markets: CEO Vlad Tenev talked about prediction markets on Friday’s episode of a NYT podcast “Hard Fork” (paywall), where he echoed a lot of Armstrong’s sentiments about prediction markets as a source of news, and shared his company’s intention to add several prediction markets later this year. Key takeaways via the Business Insider recap:
On sports betting vs. prediction markets: "I think that mechanically there's some similarities, but they're different things.”
"First of all, I think prediction markets are the future of not just trading, but also information. I've been a big believer in the power of prediction markets for a long time — kind of a student of them — and I think prediction markets should be live for everything.
"People pay for broadcast news, too, indirectly in the form of advertising. So, what prediction markets are is the news faster, right? In some cases, you get it even before it happens. So, the economic value of that as a product and service should be at least as high, and I would argue strictly greater, than the news after it happens.
"At the end of the day, I think what you'll see is prediction markets are here to stay. I think some of the details around what types of prediction markets are classified in what category I think will be worked out, but Robinhood will play a leading role in that because I think this is like incredibly important technology.
"So we were one of the few platforms that offered the ability to trade the election and that was very successful for us. We had over half a billion contracts traded in right around a week leading up to the election, and so what you should expect from us is a comprehensive events platform that will give access to prediction markets across a wide variety of contracts later this year."
Prediction markets > ?: On election outcome predictions in a Substack post, Rajiv Sethi uses statistical analysis to show prediction markets aren’t always more accurate than statistical prediction models by looking at their relative performance in close House of Representative races (from 2024). The data shows in these contexts, over time, FiveThirtyEight performed the best, Polymarket was second-best, and the Economist statistical model performed the worst, on average. He also illustrates that trading markets can be more susceptible to overreaction and volatility than statistical prediction models. Key takeaways:
“The bottom line is this—prediction markets are a useful part of the forecasting ecosystem, especially in a rapidly changing world in which few historical regularities can be taken for granted. But they are not a magic bullet, and do not make other approaches redundant. For one thing, statistical models make their presence felt in market prices as traders observe and assess them in relation to other evidence. And many questions remain unanswered about the effects of different market designs and constraints on participation.
“It is true that markets performed somewhat better than models in predicting the winner of the American presidency. But evidence from a single event cannot be considered decisive. The analysis of competitive house races makes this abundantly clear, and points to a much more nuanced picture of the relative performance of different forecasting mechanisms.”
Whole thing here:
One trade turns $2K into $100K: According to the Kalshi blog, the guy who turned $2,683 into $105K says he saw an opportunity when “Yes” shares were surging based on nothing concrete, and he started buying “No” in size when some reporters and the market latched onto a sham news tweet claiming Senator Susan Collins announced she would support Kash Patel for FBI Director. Needless to say, he didn’t buy the tweet, but he did buy enough of the right side to score a profit of over $100,000.
CFTC Commissioner stepping down: Commissioner Christy Goldsmith Romero will step down from the Commission and retire from federal service upon Brian Quintenz’s confirmation as CFTC chair and fulfillment of her term. Goldsmith Romero said of her time in service:
“History has shown how sound regulation plays a critical role in U.S. financial markets being the envy of the world, and I am honored to have played a part in promoting U.S. markets and protecting investors and customers.”
Among a long list of accolades, the CFTC public statement said of the Commissioner: Commissioner Goldsmith Romero has been a leader at the CFTC on future of finance issues. She promoted responsible innovation and competition in the CFTC’s regulation of trading of digital assets and engaged with technology innovators. She sponsored the CFTC’s Technology Advisory Committee, to which she added technology experts in cryptocurrency, stablecoins, blockchain, digital identity, AI, fintech, and cybersecurity. The committee examined emerging technology and cyber resilience and released first-of-its-kind reports on “Decentralized Finance” and “Responsible AI in Financial Markets.”
Weakening the CFTC?: The non-profit Better Markets reacted to news reported by Bloomberg (paywalled) that about a dozen CFTC probationary employees were terminated, saying the firings “make it even harder for the CFTC to fulfill its critical mission of protecting Americans from price manipulation in commodities markets that directly impact their wallets, from gas to groceries to airfare.”
“Beyond that, these firings weaken the CFTC’s ability to properly oversee the multi-trillion-dollar derivatives markets, bringing us one step closer to another financial crash.
“America’s markets should work for the many, not the well-connected few. Many support a smaller government, but gutting an already short-staffed CFTC weakens protections for consumers and comes at the expense of every American who relies on fair prices for life’s essentials.”If the CFTC is seriously going to expand the ability of platforms to offer more prediction markets, it will clearly need more people involved, not fewer.
Quick hitters
Pope markets: Betting on the health of public figures may not fly in U.S.-based prediction market platforms (TBD), but Polymarket has five Pope-related markets available for trading at the moment.
A humble brag? Kalshi CO-founder Tarek Mansour sent a congratulatory tweet about Yaakov Roth’s new appointment at the DOJ. Mansour said of Yaakov: “Without Yaakov's legal guidance and leadership, prediction markets in America wouldn't be where they are today. He was instrumental in helping Kalshi successfully sue the federal government to legalize election markets in America for the first time in over 100 years.”
So saying a word on a talk show is an important financial instrument? Kalshi self-certified mention markets for talk show guests for initial listing on Feb. 26.
Last week, we showed you a tweet from Kalshi co-founder Luana Lopes Lara poking fun at the company’s collective lack of sports market knowledge. That tweet (below) has since been deleted. Maybe saying you don’t understand the sports for which you are offering markets is a poor idea!
