The Quick Answer
Rain stopped Iva Jovic vs Magdalena Frech on the US Open Grandstand on Tuesday night with the first set level at 4-4, and Kalshi's Set 1 Winner market spent the night open trading both answers: as of 8:07 a.m. ET Wednesday the Jovic contract had last printed at 68¢, a clear favorite, but the resting bid was 36¢, the midpoint 52.5¢, and the tape had printed as low as 26¢ before midnight and 35¢ after it. Combined 24-hour volume was about 233,800 contracts. Whether a 4-4 set should be a favorite's price or a coin flip, what the 33-cent spread is really charging you, and the retirement clause that matters more than usual on a wet court are all below.
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The Set The Market Priced Two Ways
On Sunday night Kalshi listed a WTA set market that rain froze mid-tiebreak, and the crowd priced it at 50 cents because four points of tennis leave nothing to argue about. I wrote that one up as the purest price on the board. This page is its opposite, and that is the thesis: Tuesday's rain built a second frozen set, this one stopped at 4-4 with a full two games' worth of tennis still to play, and by Wednesday morning the last trade had the 18-year-old American as a favorite of roughly two to one while the resting book said something much closer to a coin flip. Which of those is the market's real answer is the argument of this page, and I'll run the set arithmetic that settles it after the mechanics; the contract's fine print comes first, because it decides what you actually own.
First, the freeze itself. Yahoo Sports reported the sequence: with Jovic up 4-3 and Frech serving, Jovic slipped on the Grandstand court in light drizzle and could not chase the ball, Frech won the point, and the game leveled the set at 4-4. Jovic went to chair umpire Aurelie Tourte and said, "You saw me. I literally, I didn't even run for the ball," then asked, "But I can stop?" Tourte's answer is the rule: "You cannot stop during the rally. I can check before we start the point. But once we start the point, we cannot replay." Play was suspended with heavy rain across the outer courts. Eleven matches were delayed Tuesday while Arthur Ashe and Louis Armstrong sat empty for more than three hours, a decision journalist José Morgado called "absolutely remarkable" given the forecast. The WTA's official score page shows the match as suspended with 55 points played, Jovic winning 50.9 percent of them, which works out to 28 points to Frech's 27.
One point separates them on the scoreboard. The market separates them by nearly 40 cents.
How A Kalshi Set 1 Winner Contract Settles
Kalshi lists each player as her own yes/no contract under the event ticker KXWTASETWINNER-26AUG30JOVFRE-1. The Jovic contract's primary rule reads, in full: "If Iva Jovic wins set 1 in the Iva Jovic vs Magdalena Frech professional tennis match in the 2026 US Open Women Singles Round Of 128, then the market resolves to Yes." The Frech contract asks the same question with her name in it. A price in cents is the crowd's probability, so a 68¢ contract says 68 percent. Our primer on how prediction markets work covers price-as-probability if it's new to you, and the guide to betting sports on Kalshi walks through placing an order.
Two clauses in the fine print matter more here than on a normal set market. The first is the delay clause: "If this match is postponed or delayed, the market will remain open and close after the rescheduled match has finished (within two weeks)." That is why a contract Kalshi originally expected to expire Sunday afternoon now shows a Sept. 13 close date and is still trading on Wednesday morning. The second is the one I keep coming back to, because Jovic's slip is exactly the scenario it was written for: "If a retirement occurs, all markets that can be unconditionally settled based on play already completed will resolve accordingly. Any markets that cannot be unconditionally settled will resolve to Fair Market Price, as determined at the sole discretion of the Exchange." At 4-4, nothing about set one is settled. If either player retires before the set ends, whether from Tuesday's slip or a fresh one on a damp court, your Yes contract pays whatever Kalshi decides a fair price was, and you have no vote. Every other number on this page assumes the set gets finished; that clause is the reason to size a resumption trade smaller than the odds alone suggest.
The clause that matters on a wet court: a retirement before set one ends does not pay $1.00 or zero. Kalshi sets a Fair Market Price at its discretion, and the holder has no say.
The Board: Two Contracts, One Suspended Set
The full market as of 8:07 a.m. ET on Wednesday, Sept. 2, 2026:
| Contract | Bid | Ask | Last trade | Contracts (24h) | Open interest |
|---|---|---|---|---|---|
| Jovic Wins Set 1 | 36¢ | 69¢ | 68¢ | 148,693 | 127,586 |
| Frech Wins Set 1 | 21¢ | 44¢ | 29¢ | 85,106 | 67,495 |
The row to read is the Jovic line, because it says two different things at once. The last trade, 68¢, and the ask, 69¢, agree with each other, and they agree with the Frech side's 29¢ last print, since 68 and 29 add up to 97, close enough to 100 to be reading the same set. But the Jovic bid sits all the way down at 36¢. The 33-point gap between bid and ask is an overnight book with almost nobody quoting either side before the courts open, and Kalshi's own liquidity field read zero at the snapshot. The Frech side shows the same shape, a 23-point spread with the last trade sitting closer to the bid. Read the midpoints instead of the last prints and the favorite shrinks: 52.5¢ for Jovic and 32.5¢ for Frech, which sum to 85, while the two asks sum to 113. Buying both sides costs $1.13 to collect $1.00, and that 13-cent premium is the real price of touching this book before the players walk out. Note the volume, too: nearly all of the 234,000 lifetime contracts across both names traded in the last 24 hours, and open interest of about 195,000 contracts is still open, waiting on a set that resumes Wednesday.
The Hour That Traded 118,000 Contracts
The board above is the morning after. The tape from Tuesday night explains how it got there. Kalshi's per-trade record for the Jovic contract shows its first fill at 72¢ just after 1 a.m. ET Tuesday, and the price barely moved all day: 70¢ in the morning, flat at 69¢ through the afternoon on barely 60 contracts, and 67¢ to 70¢ in the 8 p.m. hour as the match approached. Then, judging by the volume, the set got underway. In the single hour from 9 p.m. to 10 p.m. ET, 118,190 contracts changed hands on the Jovic side alone, about 79 percent of everything the contract has ever traded, and the price printed as low as 17¢ and as high as 88¢ inside those 60 minutes. A 17¢ print means that for at least one fill the crowd rated her chance of taking the set at about one in six; whatever the game score was at that moment, the 69¢ prior had been abandoned entirely and rebuilt inside a single hour. The largest single fill of the night, 8,612 contracts, went through at 88¢ at 9:57 p.m., nearly four minutes before a 6,184-contract print at 67¢.
The hourly tape, Eastern time, tells it in four rows:
| Window (ET, Sept. 1-2) | Jovic contracts traded | Low | High |
|---|---|---|---|
| 1 A.m. To 9 P.m. Tuesday (Pre-Match) | 3,453 | 67¢ | 73¢ |
| 9 P.m. Hour (In Play) | 118,190 | 17¢ | 88¢ |
| 10 P.m. Hour (Volume Drop-Off) | 24,254 | 34¢ | 73¢ |
| 11 P.m. Tuesday To 8:40 A.m. Wednesday | 2,973 | 26¢ | 69¢ |
After all of that, the tape did not settle on one answer. The 6,184-contract fill at 67¢ at 10:00 p.m. looked like the market returning to its pre-match prior, but the same 10 p.m. hour then printed down to 34¢ on 24,254 contracts, the 11 p.m. hour touched 26¢ on a 37-contract fill at 11:21 p.m., and the small hours never made up their mind: the 1 a.m. and 2 a.m. hours ranged from 36¢ to 69¢ on a few hundred contracts, the 4 a.m. hour traded 816 contracts between 35¢ and 55¢, with a 400-contract fill at 54¢ and 272 more at 35¢ inside the same minute, and the 5 a.m. hour's only fill, seven contracts, printed at exactly 50¢. The 68¢ last trade on the 8:07 a.m. board was set by a single seven-contract fill at 6:35 a.m., after one more contract at 50¢ earlier that hour. The book then added 134 contracts at 68¢ to 69¢ at 8:09 and 8:36 a.m., after the snapshot, which is why the table's last row runs to 8:40. So the 68¢ headline number is a seven-contract morning print on top of a night that traded the set as a coin flip more often than as a favorite. That is what a book looks like when only the impatient are in it, and it is why the midpoint, not the last trade, is the honest read of this board.
Is 4-4 A Coin Flip? The Arithmetic Says Almost
Now the arithmetic I promised. Frech served the game that made it 4-4, so by the service rotation Jovic serves the ninth and eleventh games, Frech the tenth and twelfth, and Jovic serves first if it reaches a 6-6 tiebreak. From 4-4, the set ends inside two games only if one player wins both; a hold each way makes it 5-5 and the rotation repeats. None of that order is worth anything on its own: give both women the same chance of winning a point on serve and a set from 4-4 with Jovic serving first comes out at exactly 50 percent, tiebreak included. The only thing that moves the number is a real gap in how often each player holds, so the question is how big a gap the 68¢ print is assuming.
The résumé supplies the gap. Jovic is the No. 14 seed, sitting at a career-high ranking as of Aug. 24, an 18-year-old from Torrance, California, who beat No. 8 Jasmine Paolini in the third round of the Australian Open in January, her first top-10 win, on the way to the quarterfinals. Frech is 28, ranked No. 41 as of Aug. 31, a former top-25 player with one WTA title, the 2024 Guadalajara Open, and a runner-up finish at this year's Mérida Open. The two have never played. Jovic is 9-3 in 2026 Grand Slam matches with losses only to Sabalenka, Osaka and Pegula; Frech is 2-3, and last year's third-round run here is her best US Open. So I ran the set from 4-4 under a few illustrative serve splits, using standard game and tiebreak scoring with Jovic serving first. These are assumptions, not measured rates for this match, and that is the point: they show how much asymmetry each price requires.
| Points Won On Serve (Jovic / Frech, Assumed) | Jovic holds | Frech holds | Jovic wins set 1 from 4-4 |
|---|---|---|---|
| 60% / 60% | 74% | 74% | 50% |
| 62% / 58% | 78% | 69% | 59% |
| 64% / 58% | 81% | 69% | 64% |
| 65% / 56% | 83% | 65% | 70% |
The row that matters is the bottom one. To justify the 68¢ to 69¢ price, you need Jovic holding serve roughly five times in six while Frech holds barely two times in three, a gap you would expect between a top-15 player and a qualifier, not between two women who just split 55 points 28 to 27. A gap the size of their rankings and 2026 records, something like the second or third row, lands in the high 50s to low 60s. That is well above the 52.5¢ midpoint and well below the 68¢ last print, which is another way of saying both overnight answers were wrong and the truth sat between them. If I were quoting this market, that is the band I would quote, and I would let the 69¢ ask and the 36¢ bid both come to me.
The Birrell vs Marcinko tiebreak stopped at 3-3 with as few as four points left, and the market priced it at 50 because four points is too small a sample for a ranking gap to show up in. This set stopped with at least two full games left, roughly eight points minimum and often many more, enough tennis for a real hold gap to matter, which is why the arithmetic lands above 50 rather than on it. Same tournament, same week, same contract type. The only variable that changed was how much tennis was left, and that is the whole difference between a coin flip and a modest favorite. A short-fuse market is only as sharp as the sample it has left to price.
A Worked Example: What 69¢ Buys You At 4-4
Say you agree with the last print and want Jovic. On Wednesday morning you can't buy her at the 68¢ she last traded at; the ask is 69¢. One hundred Yes contracts cost $69 and pay $100 if she wins the set, a profit of $31 on a set the last print says she wins about seven times in ten and my table says she wins closer to six. In payout terms, a 69-cent contract turns $100 into about $145 when it hits and nothing when it doesn't. The seller across from you at 69¢ is taking the Jovic No side at 31¢, which pays $1.00 if she fails to win the set, and needs that to happen more than 31 percent of the time to profit.
Now say you side with the midpoint and think a 4-4 set is closer to even than the last print does. The Frech ask is 44¢, which is a very different price from her 29¢ last trade: 100 contracts cost $44 and pay $100, a profit of $56 if she wins the set. Buying at 44 means you are paying for 44 percent on a contract the last trader valued at 29. That 15-cent difference is the cost of crossing a sleeping book, not a statement about Frech, and it is why patient traders quote a market like this at their own price and wait rather than lift the ask. Sitting on a bid instead of lifting an ask is the core of how to win on Kalshi. Re-run the arithmetic at whatever price is actually on the screen when the Grandstand opens; the third match there is listed not before 11 a.m. ET, and every number above will have moved by the time the first serve lands.
One legal note before anyone opens an account to trade the resumption: Kalshi is a CFTC-regulated exchange, it's 18+, and as of September 2026 it isn't available in every state. New York's attorney general sued Kalshi on July 31 claiming it is an illegal gambling operation, and that fight is pending. We track where prediction markets stand legally; check your state before you trade.
If pricing two games of somebody else's suspended set isn't your edge, OddsShopper's free expert picks cover full matches with full information, which two frozen games will never offer. Our experts' US Open betting picks cover the tournament the conventional way, and our comparison of US Open odds across Kalshi, Polymarket, and the sportsbooks maps the wider board this contract sits on.
Frequently Asked Questions
What is the score in Jovic vs Frech, and when does the match resume? Play was suspended by rain Tuesday night, Sept. 1, with the first set level at 4-4 after 55 points. The match is listed third on the Grandstand for Wednesday, Sept. 2, not before 11 a.m. ET, with Jovic due to serve first.
What are the Kalshi odds for the Jovic vs Frech Set 1 Winner market? As of 8:07 a.m. ET Wednesday, the Jovic contract was quoted 36¢ bid / 69¢ ask with a last trade of 68¢, and the Frech contract 21¢ / 44¢ with a last trade of 29¢. Combined 24-hour volume across the two names was about 233,800 contracts.
Does the Set 1 Winner contract pay if Jovic wins the set but loses the match? Yes. Each contract resolves purely on who wins set one. A Jovic set-one win pays her Yes holders in full even if Frech wins the next two sets.
What happens to the contract if a player retires before the set ends? Under Kalshi's rules, a market that cannot be settled from play already completed resolves to a Fair Market Price set at the exchange's sole discretion. A retirement at 4-4 would trigger that clause, so neither contract necessarily pays $1.00 or goes to zero.
Is Kalshi legal to use? Kalshi is a CFTC-regulated exchange and is 18+, but it isn't available in every state and faces active legal challenges, including New York's July 31 lawsuit. Check your own state's status before trading.
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What Wednesday Will Show
The one number to watch is the Jovic bid. It spent the night at 36¢ while the ask sat at 69¢, and the set-from-4-4 arithmetic above says the honest price lives in the high 50s to low 60s. If the bid has not cleared 45¢ by the time the Grandstand's third match is called, the book is still pricing this set closer to the small-hours coin flip than to the 68¢ print, and the seven contracts that set that print will have told you more about the market than the 233,800 that came before them. Then the ninth game, Jovic serving, either confirms the gap the table needs or erases it, and the retirement clause stays in force until the set ends, whatever the scoreboard says.
